Campbell et al's study of targeted screening for peripheral vascular disease (PVD) in patients with hypertension aged 60 years or over1 yielded, as they acknowledge, a surprisingly low prevalence of 8% with PVD, as defined by an ankle-brachial pressure index ≤0.9. Leng et al's previous Scottish study of 11 practices revealed a prevalence by the same definition of 18.2% for participants aged 55 to 74 years.2I have also recently reported a prevalence in hypertensives of 20% from my practice (mean age 70 years) as part of a study of the interarm blood pressure difference as an indicator of PVD,3 and also showed that the use of a simple tiptoe stress test4 was feasible and increased the overall detection of prevalence to 25%.
These prevalences are significantly higher than Campbell et al's finding and would clearly make a stronger case for targeted screening in primary care. The authors assert that their practice prevalence rates for hypertension are similar to average Scottish figures, yet the study profile suggests a prevalence of hypertension of 28% in their over 60s. Scottish public health data suggest a prevalence 33% for adults aged over 16, and that 75% are hypertensive above age 75.5 Other recent estimates for prevalence of hypertension exceed 60% in the over 60s.6
Therefore we suggest that the prevalence of hypertension was low for the age group included in this study, which would suggest that many cases of PVD have gone undetected as they were not included in the study. Consequently, the case for targeted screening has been understated and further work is required. This should include assessment of the peripheral circulation with exercise.
- © British Journal of General Practice, 2007.
