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Diabetes mellitus is the most common cause of kidney failure that progresses to end stage renal disease (ESRD,) meaning that the person requires dialysis or kidney transplant. ESRD is chronic and life long, is complicated to treat, has a major negative effect on quality of life and the costs are high.
So it was good news when the Centers of Disease Control reported that the incidence of ESRD among diabetics had declined by about 35% over the ten years ending in 2007. The reasons for the decline are not known but a few assumptions seem reasonable. More and more patients now keep good control of their blood sugar with careful monitoring and many also keep their blood pressure under control with anti-hypertensive medications. Further, it has been shown that angiotensin-converting enzyme inhibitors (or ACE inhibitors) and angiotensin-receptor blockers (or ARBs) slow the decline of kidney function in those with diabetes and early kidney failure. It is believed that as many as 80% of these patients are taking ACE or ARBs – a good thing. All of these may be the factors that have led to this decline of diabetes to kidney failure; or there may be others as yet not appreciated.
But the news really is not so good. The decline in kidney failure incidence was offset by a much increased absolute number of individuals with diabetes developing kidney failure. Why? Because there are so many more individuals developing diabetes now than just a decade ago – so there are more people at risk of and therefore developing kidney failure.
We can be pleased that secondary prevention approaches are slowing the onset of kidney failure among those with diabetes but we should be aghast that so many of our fellow citizens are setting themselves up for a high risk of diabetes as a result of obesity.
The message - the real need is to accelerate efforts to stop the epidemic of obesity (excess consumption of not very nutritious food compounded with a sedentary lifestyle, including in adolescents.) Obesity is the primary culprit leasing to the rapidly rising number of individuals with diabetes.
Monday, January 17, 2011
Friday, January 14, 2011
The Shingles (Herpes Zoster) Vaccine Really Works But Many Older Folks Don’t Receive It - They Should
Herpes zoster (or shingles) is caused by the same virus that causes chicken pox. Zoster increases in incidence with advancing age. It is estimated that over 1 million Americans get shingles annually with the resulting acute discomfort and often chronic pain thereafter. A vaccine was introduced by Merck in 2006; the initial studies of 38,546 patients indicated that it reduced the incidence by about 50% and for those who still got shingles, the severity was lessened substantially. But acceptance of the vaccine has been slow. It seems that this is due to a combination of lack of knowledge that it is available and is effective; failure of physicians to inform their patients; and a fairly high cost of about $200, often not covered by insurance.
A new study was reported in JAMA January 12, 2011. Kaiser Permanente, Southern California and Centers for Disease Control and Prevention investigators evaluated 75,761 Kaiser members who had no underlying immunological disorder and who had been vaccinated between January, 2007 and December 2009. These were compared to a control group of 227,283 age matched members who had not been vaccinated.
Among the unvaccinated individuals, this study showed that, as anticipated, shingles incidence goes up with age from - 60-64 years of age (9.7 infections per 1000 person years) to over age 80 (17.3 per 1000 person years).
Vaccination reduced the frequency by about 50% from a total of 13.0 per 1000 person years to 6.4 per 1000 person years. This halving of incidence was found at all age intervals, indicating that the vaccine works as well in the very elderly as in “younger” individuals. The incidence of zoster was steady over time. For example, at one year, slightly more that 1% of the unvaccinated individuals had developed zoster compared to less that 0.05% in the vaccinated group; at two years the numbers were about 2 ½ % and 1%, respectively. During the time of patient follow-up, this can be stated as one case of herpes zoster was prevented with each 71 vaccinated. However, since the follow up was only about 1 ½ years for most individuals and since it is estimated that beginning at age 60 a person has a 20% lifetime risk of zoster, it is my presumption that it actually takes many fewer individuals vaccinated to prevent one episode of zoster over the rest of one’s life.
Not part of this study, the original Merck investigation demonstrated that many older people do not respond well to the vaccine with increases in antibody production. This finding is consistent with many others that those over 60 years of age respond much less well than do those who are younger. This raises the question as to whether it would be useful to measure antibody production after vaccination to determine who has and who has not responded well. Perhaps those who do not should get a second vaccination. This is an important issue for all vaccines in older people. The same occurs with influenza vaccine which is why, this year, the dose for older people was doubled. But perhaps there are other approaches as well to improving the response rates for those at increased risk in their older years who respond less well to vaccines.
The study makes clear that this vaccine is effective, including for those over 80 years of age where the incidence is the highest. Given the implications of herpes zoster in immediate and longer term suffering and the attendant costs, I believe this is a vaccine that essentially everyone over the age of 60 (other than immunocompromised individuals) should receive. Insurance should pay for it just as with the influenza vaccine.
Even if paid for out of pocket, it is worth it. Patients need to ask for it and doctors need to encourage it.
A new study was reported in JAMA January 12, 2011. Kaiser Permanente, Southern California and Centers for Disease Control and Prevention investigators evaluated 75,761 Kaiser members who had no underlying immunological disorder and who had been vaccinated between January, 2007 and December 2009. These were compared to a control group of 227,283 age matched members who had not been vaccinated.
Among the unvaccinated individuals, this study showed that, as anticipated, shingles incidence goes up with age from - 60-64 years of age (9.7 infections per 1000 person years) to over age 80 (17.3 per 1000 person years).
Vaccination reduced the frequency by about 50% from a total of 13.0 per 1000 person years to 6.4 per 1000 person years. This halving of incidence was found at all age intervals, indicating that the vaccine works as well in the very elderly as in “younger” individuals. The incidence of zoster was steady over time. For example, at one year, slightly more that 1% of the unvaccinated individuals had developed zoster compared to less that 0.05% in the vaccinated group; at two years the numbers were about 2 ½ % and 1%, respectively. During the time of patient follow-up, this can be stated as one case of herpes zoster was prevented with each 71 vaccinated. However, since the follow up was only about 1 ½ years for most individuals and since it is estimated that beginning at age 60 a person has a 20% lifetime risk of zoster, it is my presumption that it actually takes many fewer individuals vaccinated to prevent one episode of zoster over the rest of one’s life.
Not part of this study, the original Merck investigation demonstrated that many older people do not respond well to the vaccine with increases in antibody production. This finding is consistent with many others that those over 60 years of age respond much less well than do those who are younger. This raises the question as to whether it would be useful to measure antibody production after vaccination to determine who has and who has not responded well. Perhaps those who do not should get a second vaccination. This is an important issue for all vaccines in older people. The same occurs with influenza vaccine which is why, this year, the dose for older people was doubled. But perhaps there are other approaches as well to improving the response rates for those at increased risk in their older years who respond less well to vaccines.
The study makes clear that this vaccine is effective, including for those over 80 years of age where the incidence is the highest. Given the implications of herpes zoster in immediate and longer term suffering and the attendant costs, I believe this is a vaccine that essentially everyone over the age of 60 (other than immunocompromised individuals) should receive. Insurance should pay for it just as with the influenza vaccine.
Even if paid for out of pocket, it is worth it. Patients need to ask for it and doctors need to encourage it.
Tuesday, January 11, 2011
To Scan or Not To Scan for Early Lung Cancer
Lung cancer is the most common cancer other than skin cancer. The survival rate is still dismal so early diagnosis presumably could make an impact. Chest x-rays just do not have the sensitivity to find early lung cancer. Computed tomography (CT Scans) can detect very small lesions in the lung. Another study has now been completed and it was able to find many early cancers.
The National Cancer Institute funded this study that randomly allocated some 53,500 men and women at high risk (i.e., smoked about 1 pack or more cigarettes per day for 30 or more years) to either standard chest X-rays or low dose CT scans. Each person had a screening image taken annually for three years and were followed for an additional five years.
As of October, 2010, there were 649 cancers detected and 354 deaths in the CT group compared to 279 cancers and 442 lung cancer deaths in the X-ray group (obviously many of these latter cancer deaths were due to cancer NOT detected by the routine chest X-ray). The implication is that low dose CT scans detected cancer earlier resulting in successful therapy for many.
Lung cancer mortality per 100,000 was 246 and 308 for the CT group and the X-ray group respectively for a 20% reduction in lung cancer mortality.
But there are “buts” to the study. To save one life required 300 people to be screened. A CT scan costs at least $300 each, often much more. This means it cost $90,000 to save one life. Another “but” is CT screening detects lesions that are often not cancer. Indeed the false positive rate was about 25%. Since it requires a biopsy to prove it is benign, this adds not only risk and costs, but anxiety.
There is more information at http://tinyurl.com/2cutflw
The take away for now is that in high risk individuals, low dose CT scans can pick up early lung cancer. But the combination of high false positives and high costs weigh against its routine use even in these patients.
The National Cancer Institute funded this study that randomly allocated some 53,500 men and women at high risk (i.e., smoked about 1 pack or more cigarettes per day for 30 or more years) to either standard chest X-rays or low dose CT scans. Each person had a screening image taken annually for three years and were followed for an additional five years.
As of October, 2010, there were 649 cancers detected and 354 deaths in the CT group compared to 279 cancers and 442 lung cancer deaths in the X-ray group (obviously many of these latter cancer deaths were due to cancer NOT detected by the routine chest X-ray). The implication is that low dose CT scans detected cancer earlier resulting in successful therapy for many.
Lung cancer mortality per 100,000 was 246 and 308 for the CT group and the X-ray group respectively for a 20% reduction in lung cancer mortality.
But there are “buts” to the study. To save one life required 300 people to be screened. A CT scan costs at least $300 each, often much more. This means it cost $90,000 to save one life. Another “but” is CT screening detects lesions that are often not cancer. Indeed the false positive rate was about 25%. Since it requires a biopsy to prove it is benign, this adds not only risk and costs, but anxiety.
There is more information at http://tinyurl.com/2cutflw
The take away for now is that in high risk individuals, low dose CT scans can pick up early lung cancer. But the combination of high false positives and high costs weigh against its routine use even in these patients.
Tuesday, December 14, 2010
Hospitals are Unsafe - There Are Still Plenty of Preventable Medical Errors
Over the past ten years and since the publication of the Institute of Medicine landmark book “To Err Is Human” there have been many attempts to reduce preventable medical errors which are estimated to take about 100,000 lives per year – perhaps many more. The question is whether all of this effort has had a substantial clinical impact.
The results of a recently published study are therefore concerning. A group lead by Dr Landrigan at Harvard evaluated the number of “harms” which occurred at ten randomly selected North Carolina hospitals. They taught a cadre of reviewers to use “triggers” in the medical record to prompt further analysis for an error that caused harm. The harms were categorized into five groups with E being temporary yet requiring an intervention through, F temporary but requiring initial or prolonged hospitalization, G permanent harm, H as life threatening harm and I causing or contributing to death. They then selected 10 records per quarter for the years 2002 through 2007 from each hospital, at random. The records were then reviewed in a random order by multiple internal and external trained reviewers, both nurses and doctors.
They found 588 harms among the 10,415 patient days or 57 harms/1000 days or 25 harms per 100 admissions. About 63% or 364 of the 588 harms were classified as preventable! These included 13 that caused permanent injury, 35 being life threatening and 9 contributing or leading to death.
Similar to prior studies, the harms occurred most frequently after procedures and medications. Most harms fell into categories E (144) and F (163).
It was disappointing to find that the rates of adverse events did not decline over the study time period. This, despite the fact that in North Carolina has an enviable record of a high level of engagement in patient safety programs and studies.
So there are still plenty of adverse events that occur in a hospital, they are most likely to be related to procedures or medications, most are preventable, and all too many are life threatening or lead to death.
This leads to the question of whether the many and various approaches that hospitals have embarked upon are actually doing what they need to do. It may be time for a reappraisal. Certainly a patient should have the expectation of not being harmed when in the hospital.
The results of a recently published study are therefore concerning. A group lead by Dr Landrigan at Harvard evaluated the number of “harms” which occurred at ten randomly selected North Carolina hospitals. They taught a cadre of reviewers to use “triggers” in the medical record to prompt further analysis for an error that caused harm. The harms were categorized into five groups with E being temporary yet requiring an intervention through, F temporary but requiring initial or prolonged hospitalization, G permanent harm, H as life threatening harm and I causing or contributing to death. They then selected 10 records per quarter for the years 2002 through 2007 from each hospital, at random. The records were then reviewed in a random order by multiple internal and external trained reviewers, both nurses and doctors.
They found 588 harms among the 10,415 patient days or 57 harms/1000 days or 25 harms per 100 admissions. About 63% or 364 of the 588 harms were classified as preventable! These included 13 that caused permanent injury, 35 being life threatening and 9 contributing or leading to death.
Similar to prior studies, the harms occurred most frequently after procedures and medications. Most harms fell into categories E (144) and F (163).
It was disappointing to find that the rates of adverse events did not decline over the study time period. This, despite the fact that in North Carolina has an enviable record of a high level of engagement in patient safety programs and studies.
So there are still plenty of adverse events that occur in a hospital, they are most likely to be related to procedures or medications, most are preventable, and all too many are life threatening or lead to death.
This leads to the question of whether the many and various approaches that hospitals have embarked upon are actually doing what they need to do. It may be time for a reappraisal. Certainly a patient should have the expectation of not being harmed when in the hospital.
Wednesday, December 8, 2010
Two Treatments For Macular Degeneration – At Wildly Divergent Costs
Age-related macular degeneration (AMD) is the leading cause of blindness in the United States. More than 1 million Americans have neovascular or “wet” AMD and a slightly lower number have “dry” AMD which often progresses to the more severe “wet” form. Since this is a disease of aging, we can expect many more cases as the population expands in the coming years.
Neovascular AMD appears to be related, at lease in part, to excess production of vascular endothelial growth factor (VEGF-A.) A specially developed monoclonal antibody called ranibizumab is available and approved by the FDA for wet AMD. The monoclonal antibody binds to VEGF-A, blocking function and thereby allowing healing of the retina. As a result of decreased vessel growth and decreased leakage, vision can stabilize and frequently actually improve. (See the clinical therapeutics article by Folk and Stone in the New England Journal of Medicine 2010; 363:1648 - 1655 for more details.)
Ranibizumab is injected directly into the eye and an effective concentration lasts for about 30 days. Although not a trivial procedure, it is straight forward in experienced hands and takes but a few minutes in an outpatient setting under topical and local anesthesia. The procedure is repeated in four weeks and in four weeks again. If vision has stabilized or even improved, then the next visit is scheduled in five weeks, then six weeks, etc. It appears that most treatment failures relate to missed follow-ups so attention to timing is very critical.
There is another anti VEGF-A monoclonal antibody, called bevacizumab, approved by the FDA for use in metastatic colon cancer treatment. It costs about $75 for a 1.25 milligram dose whereas ranibizumab costs about $2000 for a comparable dose (0.5 mg.) Although clearly an “off label” use, many retinal specialists will offer bevacizumab as an alternative to ranibizumab and let the patients ultimately decide. Trials comparing the two drugs are underway with results expected in less than a year.
What is clear now is the intraocular injections of anti-VEGF-A monoclonal antibody has substantial efficacy with limited risk.
Wednesday, December 1, 2010
Replacing the Aortic Valve Without Open Surgery!
Aortic stenosis (a narrowing and hardening of the heart’s aortic valve) is not uncommon among older individuals. It begins without symptoms and progresses for years but, about 50% will die within 2 years once the fitst symptoms develop. The standard approach is to surgically replace the aortic valve which will improve both heart function and survival. Unfortunately, about 30% of symptomatic individuals cannot undergo surgery because of older age, other heart problems or other medical conditions that render surgery too risky.
A new approach is called transcatheter aortic value implantation (TAVI.) In this procedure, a catheter is inserted into the large femoral artery in the groin and run up to the heart. From the catheter, the patient’s valve is opened wide with an inflatable balloon. Then a bioprosthetic value made from bovine pericardium affixed to a stainless steel support frame is deployed into place via another balloon catheter and secured to patient’s own aortic valve base.
A randomized study of 358 patients with aortic stenosis not considered surgical candidates was completed comparing TAVI to standard therapy at 21 medical centers and reported in the New England Journal of Medicine on October 21, 2010. The results were clearly favorable. Standard therapy was noted to not alter the natural history of aortic stenosis with 51% dead in one year. TAVI was superior with improved cardiac symptoms and good hemodynamic performance of the new valve which persisted for at least the first year of follow-up and with 31% dying during that year, a substantial decline in mortality.
But there is never a “free lunch” and TAVI was associated with a 5% risk of serious stroke (compared to 1% in the control group) and multiple vascular complications, the latter apparently related to the requirement for a large catheter placed into the femoral artery. Further MRI studies of patients suggest that many have new perfusion defects of the brain after TAVI suggesting that emboli from the new valve may be rather common.
But all things considered the improvement in symptoms and the reduced death rate (it took only 5 patients treated with TAVI to avoid one death by 1 year) argue that TAVI is now the appropriate therapeutic approach for those with aortic stenosis who cannot otherwise undergo surgery. Hopefully, coming improvements in the device will lead to fewer complications.
The big question – will this become the approach of choice for those who otherwise are candidates for standard surgery for aortic valve replacement?
A new approach is called transcatheter aortic value implantation (TAVI.) In this procedure, a catheter is inserted into the large femoral artery in the groin and run up to the heart. From the catheter, the patient’s valve is opened wide with an inflatable balloon. Then a bioprosthetic value made from bovine pericardium affixed to a stainless steel support frame is deployed into place via another balloon catheter and secured to patient’s own aortic valve base.
A randomized study of 358 patients with aortic stenosis not considered surgical candidates was completed comparing TAVI to standard therapy at 21 medical centers and reported in the New England Journal of Medicine on October 21, 2010. The results were clearly favorable. Standard therapy was noted to not alter the natural history of aortic stenosis with 51% dead in one year. TAVI was superior with improved cardiac symptoms and good hemodynamic performance of the new valve which persisted for at least the first year of follow-up and with 31% dying during that year, a substantial decline in mortality.
But there is never a “free lunch” and TAVI was associated with a 5% risk of serious stroke (compared to 1% in the control group) and multiple vascular complications, the latter apparently related to the requirement for a large catheter placed into the femoral artery. Further MRI studies of patients suggest that many have new perfusion defects of the brain after TAVI suggesting that emboli from the new valve may be rather common.
But all things considered the improvement in symptoms and the reduced death rate (it took only 5 patients treated with TAVI to avoid one death by 1 year) argue that TAVI is now the appropriate therapeutic approach for those with aortic stenosis who cannot otherwise undergo surgery. Hopefully, coming improvements in the device will lead to fewer complications.
The big question – will this become the approach of choice for those who otherwise are candidates for standard surgery for aortic valve replacement?
Sunday, November 14, 2010
Teamwork Improves Surgical Safety and Reduces Mortality
Like the cockpit, the operating room (OR) is fraught with high intensity, high complexity, high velocity, and high stakes. And as a capital intense location which serves as the financial engine of many or not most hospitals, there is pressure to use the OR efficiently. Like the cockpit, there is hierarchy, and a deep culture which includes strongly held rituals and customs. Unfortunately, there are also errors of omission and commission which lead to adverse outcomes including patient mortality.
Airlines have proven that teamwork in the cockpit improves safety substantially to the extent that commercial airlines demand and licensing now requires evidence of team competency.
Some hospitals have used the airline team training model – called crew resource management – to improve teamwork in the OR. The Veterans Health Administration (VHA) has 130 hospitals providing surgery and in 2006 mandated team training nationwide. Since it took time to arrange the training for each hospital, a study was instituted to compare surgical mortality between those hospitals which had already undergone training and those which had yet to do so (Journal of the American Medical Association, Oct 20, 2010 – both the article and accompanying editorial.)
The mandatory team training included working as a team, challenging each other as to perceived risks or safety lapses, checklist guidance, and preoperative briefing and post operative debriefing. Team members were also taught various communication strategies, how to step back and reassess, how to communicate during care transitions and basic rules of conduct.
The major measure was surgical mortality which was reduced by 18% in the 74 hospitals that had received the training compared to a 7% reduction in the 34 hospitals yet untrained (the controls.) The risk-adjusted mortality rates dropped from 17 per 1000 patients before training to 14 after training.
The study demonstrated the value of team training in reducing mortality. I would add that, although not studied, it is likely that errors were reduced overall. Surgical teams are often excellent at responding to problems including those resultant from human error. Reducing mortality was obviously important, indeed very important, but reducing preventable errors overall – as I will presume occurred – will have meant a better outcome for many patients.
The concept of team training is relevant not just in the OR but in many hospital settings such as bedside patient care rounds and with procedures done in the cardiac As I have written about before, the more team training is fostered, and indeed mandated, the lower will be the rate of preventable errors.
Airlines have proven that teamwork in the cockpit improves safety substantially to the extent that commercial airlines demand and licensing now requires evidence of team competency.
Some hospitals have used the airline team training model – called crew resource management – to improve teamwork in the OR. The Veterans Health Administration (VHA) has 130 hospitals providing surgery and in 2006 mandated team training nationwide. Since it took time to arrange the training for each hospital, a study was instituted to compare surgical mortality between those hospitals which had already undergone training and those which had yet to do so (Journal of the American Medical Association, Oct 20, 2010 – both the article and accompanying editorial.)
The mandatory team training included working as a team, challenging each other as to perceived risks or safety lapses, checklist guidance, and preoperative briefing and post operative debriefing. Team members were also taught various communication strategies, how to step back and reassess, how to communicate during care transitions and basic rules of conduct.
The major measure was surgical mortality which was reduced by 18% in the 74 hospitals that had received the training compared to a 7% reduction in the 34 hospitals yet untrained (the controls.) The risk-adjusted mortality rates dropped from 17 per 1000 patients before training to 14 after training.
The study demonstrated the value of team training in reducing mortality. I would add that, although not studied, it is likely that errors were reduced overall. Surgical teams are often excellent at responding to problems including those resultant from human error. Reducing mortality was obviously important, indeed very important, but reducing preventable errors overall – as I will presume occurred – will have meant a better outcome for many patients.
The concept of team training is relevant not just in the OR but in many hospital settings such as bedside patient care rounds and with procedures done in the cardiac As I have written about before, the more team training is fostered, and indeed mandated, the lower will be the rate of preventable errors.
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