Hubertus G. M. Leufkens

Differences in the availability of medicines for chronic and acute conditions in the public and private sectors of developing countries

OBJECTIVE To investigate potential differences in the availability of medicines for chronic and acute conditions in low- and middle-income countries. METHODS Data on the availability of 30 commonly-surveyed medicines - 15 for acute and 15 for chronic conditions - were obtained from facility-based surveys conducted in 40 developing countries. Results were aggregated by World Bank country income group and World Health Organization region. FINDINGS The availability of medicines for both acute and chronic conditions was suboptimal across countries, particularly in the public sector. Generic medicines for chronic conditions were significantly less available than generic medicines for acute conditions in both the public sector (36.0% availability versus 53.5%; P = 0.001) and the private sector (54.7% versus 66.2%; P = 0.007). Antiasthmatics, antiepileptics and antidepressants, followed by antihypertensives, were the drivers of the observed differences. An inverse association was found between country income level and the availability gap between groups of medicines, particularly in the public sector. In low- and lower-middle income countries, drugs for acute conditions were 33.9% and 12.9% more available, respectively, in the public sector than medicines for chronic conditions. Differences in availability were smaller in the private sector than in the public sector in all country income groups. CONCLUSION Current disease patterns do not explain the significant gaps observed in the availability of medicines for chronic and acute conditions. Measures are needed to better respond to the epidemiological transition towards chronic conditions in developing countries alongside current efforts to scale up treatment for communicable diseases.

Genetic polymorphisms: importance for response to HMG-CoA reductase inhibitors

Coronary artery disease is among the leading causes of death worldwide. Clinical trials show a protective effect of statins against the sequelae of coronary artery disease. The mean risk reductions for subjects using statins compared with placebo found in these trials is about 30%. These are average reductions for all patients included in the trials. Important factors in interpreting the variability in the outcome of drug therapy include the patients health profile, prognosis, disease severity, quality of drug prescribing, compliance with prescribed pharmacotherapy and the genetic profile of the patient. This review aims to give an overview of the known polymorphisms (Cholesteryl Ester Transfer Protein polymorphism, Stromelysin-1 polymorphism, -455G/A and TaqI polymorphisms of the beta-fibrinogen gene, apoE4, Asp(9)Asn mutation in the lipoprotein lipase gene, the -514 CT polymorphism in the hepatic lipase gene and the ACE deletion type gene) that have an influence on the effects of statins in the general population. The expectation is that in the future a subjects genotype may determine whether he will be treated with statins or not. Determining the genotype will not deny therapy to a subject, but will help in deciding the therapy that will suit the patient best.

Timing of Acute Myocardial Infarction in Patients Undergoing Total Hip or Knee Replacement A Nationwide Cohort Study

BACKGROUND Limited evidence suggests that the risk of acute myocardial infarction (AMI) may be increased shortly after total hip replacement (THR) and total knee replacement (TKR) surgery. However, risk of AMI in these patients has not been compared against matched controls who have not undergone surgery. The objective of this study was to evaluate the timing of AMI in patients undergoing THR or TKR surgery compared with matched controls. METHODS Retrospective, nationwide cohort study within the Danish national registries. All patients who underwent a primary THR or TKR (n = 95,227) surgery from January 1, 1998, through December 31, 2007, were selected and matched to 3 controls (no THR or TKR) by age, sex, and geographic region. All study participants were followed up for AMI, and disease- and medication history-adjusted hazard ratios (HRs) were calculated. RESULTS During the first 2 postoperative weeks, the risk of AMI was substantially increased in THR patients compared with controls (adjusted HR, 25.5; 95% CI, 17.1-37.9). The risk remained elevated for 2 to 6 weeks after surgery (adjusted HR, 5.05; 95% CI, 3.58-7.13) and then decreased to baseline levels. For TKR patients, AMI risk was also increased during the first 2 weeks (adjusted HR, 30.9; 95% CI, 11.1-85.5) but did not differ from controls after the first 2 weeks. The absolute 6-week risk of AMI was 0.51% in THR patients and 0.21% in TKR patients. CONCLUSIONS Risk of AMI is substantially increased in the first 2 weeks after THR (25-fold) and TKR (31-fold) surgery compared with controls. Risk assessment of AMI should be considered during the first 6 weeks after THR surgery and during the first 2 weeks after TKR surgery.

Use of alpha-blockers and the risk of hip/femur fractures.

Objective.  To study the association between use of α‐blockers and risk of hip/femur fractures.

Use of oral corticosteroids and risk of fractures. June, 2000.

Treatment with oral corticosteroids is known to decrease bone density but there are few data on the attendant risk of fracture and on the reversibility of this risk after cessation of therapy. A retrospective cohort study was conducted in a general medical practice setting in the United Kingdom (using data from the General Practice Research Database [GPRD]). For each oral corticosteroid user aged 18 years or older, a control patient was selected randomly, who was matched by age, sex, and medical practice. The study comprised 244,235 oral corticosteroid users and 244,235 controls. The average age was 57.1 years in the oral corticosteroid cohort and 56.9 years in the control cohort. In both cohorts 58.6% were female. The most frequent indication for treatment was respiratory disease (40%). The relative rate of nonvertebral fracture during oral corticosteroid treatment was 1.33 (95% confidence interval [CI], 1.29–1.38), that of hip fracture 1.61 (1.47–1.76), that of forearm fracture 1.09 (1.01–1.17), and that of vertebral fracture 2.60 (2.31–2.92). A dose dependence of fracture risk was observed. With a standardized daily dose of less than 2.5 mg prednisolone, hip fracture risk was 0.99 (0.82–1.20) relative to control, rising to 1.77 (1.55–2.02) at daily doses of 2.5–7.5 mg, and 2.27 (1.94–2.66) at doses of 7.5 mg or greater. For vertebral fracture, the relative rates were 1.55 (1.20–2.01), 2.59 (2.16–3.10), and 5.18 (4.25–6.31), respectively. All fracture risks declined toward baseline rapidly after cessation of oral corticosteroid treatment. These results quantify the increased fracture risk during oral corticosteroid therapy, with greater effects on the hip and spine than forearm. They also suggest a rapid offset of this increased fracture risk on cessation of therapy, which has implications for the use of preventative agents against bone loss in patients at highest risk. (J Bone Miner Res 2000;15:993–1000)

Use of nonsteroidal anti-inflammatory drugs and risk of fractures

In animal models, prostaglandin synthesis has been found to mediate bone metabolism. Nonsteroidal anti-inflammatory drugs (NSAIDs), given their inhibitory effects of prostaglandin synthesis, may play a role in the prevention of osteoporosis. The primary objective of this study is to describe and quantify the fracture risks of patients exposed to NSAIDs in a representative general medical practice setting. A retrospective cohort study was conducted in a general medical practice setting in the UK (using data from the General Practice Research Database). Regular NSAID users (who received three or more NSAID prescriptions), aged 18 years or older, were compared with matched control patients and incidental NSAID users. The study comprised 214,577 regular NSAID users, 286,850 incidental NSAID users, and 214,577 control patients. The relative rate of nonvertebral fractures during regular NSAID treatment compared with control was 1.47 (95% confidence interval [CI] 1.42-1. 52) and that of hip fracture 1.08 (0.98-1.19). No differences in nonvertebral fractures were found between the regular and incidental NSAID users (RR = 1.04; 95% CI 0.99-1.09). The rate of nonvertebral fractures among users of diclofenac (RR = 1.00; 95% CI 0.93-1.08) and naproxen (RR = 0.91; 95% CI 0.82-1.00) was similar to that of ibuprofen. The results of this study are not supportive of clinically significant effects of NSAIDs on bone metabolism.

Use of Organic Nitrates and the Risk of Hip Fracture: A Population-Based Case-Control Study

CONTEXT Use of organic nitrates has been associated with increased bone mineral density. Moreover, a large Danish case-control study reported a decreased fracture risk. However, the association with duration of nitrate use, dose frequency, and impact of discontinuation has not been extensively studied. OBJECTIVE Our objective was to evaluate the association between organic nitrates and hip fracture risk. METHODS A case-control study was conducted using the Dutch PHARMO Record Linkage System (1991-2002, n = 6,763 hip fracture cases and 26,341 controls). Cases had their first admission for hip fracture, whereas controls had not sustained any fracture after enrollment. Current users of organic nitrates were patients who had received a prescription within 90 d before the index date. The analyses were adjusted for disease and drug history. RESULTS Current use of nitrates was not associated with a decreased risk of hip fracture [adjusted odds ratio (OR) = 0.93; 95% confidence interval (CI) = 0.83-1.04]. Those who used as-needed medication only had a lower risk of hip fracture (adjusted OR = 0.83; 95% CI = 0.63-1.08) compared with users of maintenance medication only (adjusted OR = 1.17; 95% CI = 0.97-1.40). No association was found between duration of nitrate use and fracture risk. CONCLUSIONS Our overall analyses showed that risk of a hip fracture was significantly lower among users of as-needed organic nitrates, when compared with users of maintenance medication. Our analyses of hip fracture risks with duration of use did not further support a beneficial effect of organic nitrates on hip fracture, although residual confounding may have masked beneficial effects.

Changes in mortality patterns following total hip or knee arthroplasty over the past two decades: A nationwide cohort study

Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are effective procedures for patients with moderate‐to‐severe osteoarthritis. Mortality rates after THA and TKA may have changed because of new surgical techniques, improvement of peri‐ and postoperative care, and performance of surgery in older patients having multiple comorbidities. However, data on secular mortality trends are scarce. We undertook this study to evaluate mortality patterns between 1989 and 2007 in patients undergoing elective THA and TKA.

Adherence to and dosing of beta-hydroxy-beta-methylglutaryl coenzyme A reductase inhibitors in the general population differs according to apolipoprotein E-genotypes

Discontinuation and poor adherence to therapy are major problems during long-term treatment, particularly with cholesterol lowering drugs. Several studies have indicated that the cholesterol lowering effect of statins differs according to apolipoprotein (apo)E genotypes. Low-density lipoprotein-cholesterol lowering capacity appears to be smaller in subjects with the epsilon(4) allele. To assess whether the use of statins in daily practice differs according to apoE genotypes, we used data from the Rotterdam Study, a population-based prospective cohort study in the Netherlands, which started in 1990 and included 7983 subjects aged 55 years or more. During follow-up, there were 798 subjects who started to use statins. We used a Cox proportional hazard model to determine the rate of discontinuation in the first 3 years of statin use. Subjects on statin therapy with epsilon(2)epsilon(2) and epsilon(4)epsilon(4) genotypes showed a trend towards higher dosages than subjects with the other genotypes. Relative to subjects with the epsilon(2)epsilon(3) genotype, those with the epsilon(4)epsilon(4) genotype had a risk of 2.28 [95% confidence interval (CI) 1.02-5.12] to discontinue statins within 3 years. In women, this relative risk was 1.70 (CI 0.53-5.42) versus 3.18 (CI 1.01-10.03) in men. The apoE genotype is associated with discontinuation of statins. This suggests that subjects who are genetically prone to develop hypercholesterolemia show the highest risk of discontinuation of treatment.

Pharmacoeconomic evaluation of testing for angiotensin-converting enzyme genotype before starting β-hydroxy-β-methylglutaryl coenzyme A reductase inhibitor therapy in men

This study aimed to assess the potential cost-effectiveness of screening men for their angiotensin-converting enzyme (ACE)-genotype before starting statin therapy. We used a combination of decision-analytic and Markov modelling techniques to evaluate the long-term incremental clinical and economic effects associated with genetic testing of men with hypercholesterolemia before starting treatment with statins. The study was performed from a health care payer perspective. We used data from the Rotterdam study, a prospective population-based cohort study in the Netherlands, which was started in 1990 and included 7983 subjects aged 55 years and older. Men treated with cholesterol-lowering drugs at baseline or with a baseline total cholesterol > or = 6.5 mmol/l were included. The ratio of difference in lifelong costs between the screening strategy and the no screening strategy to difference in life expectancy between these strategies was calculated. We also performed a cost-utility analysis. The base case was a 55-year-old man with hypercholesterolemia who was initially untreated. Several univariate sensitivity analyses were performed. All costs were discounted with an annual rate of 5%. Screening men for their ACE-genotype was the dominant strategy for the base case analysis, because the screening strategy saved money (851 Euro), but life expectancy was not changed. Screening was the dominant strategy for all age-groups in our cohort. Even in 80-year-old subjects, with the shortest life-expectancy, it was cheaper to screen than to give lifelong treatment to men with a DD genotype without success. Even if all DD subjects were treated with other (non-statin) cholesterol-lowering drugs, screening remained the cost-effective strategy. The results of the cost-utility analysis were similar. Discounting the effects with 5% per year also had no major impact on the conclusions. If other studies confirm that men with the DD genotype do not benefit from treatment with statins, screening for ACE genotype in men most likely will be a cost-effective strategy before initiating statin therapy.