High total serum cholesterol, medication coverage and therapeutic control: An analysis of national health examination survey data from eight countries

Abstract

Objective To determine the fraction of individuals with high total serum cholesterol who get diagnosed and effectively treated in eight high- and middle-income countries. Methods Using data from nationally representative health examination surveys conducted in 1998-2007, we studied a probability sample of 79 039 adults aged 40-79 years from England, Germany, Japan, Jordan, Mexico, Scotland, Thailand and the United States of America. For each country we calculated the prevalence of high total serum cholesterol (total serum cholesterol ≥ 6.2 mmol/l or ≥ 240 mg/dl) and the mean total serum cholesterol level. We also determined the fractions of individuals being diagnosed, treated with cholesterol-lowering medication and effectively controlled (total serum cholesterol < 6.2 mmol/l or < 240 mg/dl). Findings The proportion of undiagnosed individuals was highest in Thailand (78%; 95% confidence interval, CI: 74-82) and lowest in the United States (16%; 95% CI: 13-19). The fraction diagnosed but untreated ranged from 9% in Thailand (95% CI: 8-11) to 53% in Japan (95% CI: 50-57). The proportion being treated who had attained evidence of control ranged from 4% in Germany (95% CI: 3-5) to 58% in Mexico (95% CI: 54-63). Time series estimates showed improved control of high total serum cholesterol over the past two decades in England and the United States. Conclusion The percentage of people with high total serum cholesterol who are effectively treated remains small in selected high- and middle-income countries. Many of those affected are unaware of their condition. Untreated high blood cholesterol represents a missed opportunity in the face of a global epidemic of chronic diseases.