Lipid re-screening: what is the best measure and interval?

Journal article

OBJECTIVES: To estimate the long-term true change variation ('signal') and short-term within-person variation ('noise') of the different lipid measures and evaluate the best measure and the optimal interval for lipid re-screening. DESIGN: Retrospective cohort study from 2005 to 2008. SETTING: A medical health check-up programme at a centre for preventive medicine in a teaching hospital in Tokyo, Japan. PARTICIPANTS: 15 810 apparently healthy Japanese adults not taking cholesterol-lowering drugs at baseline, with a mean body mass index of 22.5 kg/m(2) (SD 3.2). MAIN OUTCOME MEASURES: Annual measurement of the serum total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and calculation of the ratio of TC/HDL and LDL/HDL. Measurement of the ratio of long-term true change variation ('signal') to the short-term within-person variation ('noise') for each measure. RESULTS: At baseline, participants (53% male) with a mean age of 49 years (range 21-92) and a mean TC level of 5.3 mmol/l (SD 0.9 mmol/l) had annual check-ups over 4 years. Short-term within-person variations of TC, LDL, HDL, TC/HDL, and LDL/HDL were 0.12 (coefficient of variation (CV) 6.4%), 0.08 (CV 9.4%), 0.02 (CV 8.0%) mmol(2)/l(2), 0.08 (CV 7.9%) and 0.05 (CV 10.6%), respectively. The ratio of signal-to-noise at 3 years was largest for TC/HDL (1.6), followed by LDL/HDL (1.5), LDL (0.99), TC (0.8) and HDL (0.7), suggesting that cholesterol ratios are more sensitive re-screening measures. CONCLUSION: The signal-to-noise ratios of standard single lipid measures (TC, LDL and HDL) are weak over 3 years and decisions based on these measures are potentially misleading. The ratios, TC/HDL and LDL/HDL, seem to be better measures for monitoring assessments. The lipid re-screening interval should be >3 years for those not taking cholesterol-lowering drugs.

Authors: Takahashi, O; Glasziou, P; Perera, R; Shimbo, T; Suwa, J

• Publication status: Published
• Journal: Heart (British Cardiac Society)
• Volume: 96
• Issue: 6
• Pages: 448-452
• Publication date: 2010-03-01
• DOI: 10.1136/hrt.2009.172619
• EISSN: 1468-201X
• ISSN: 1355-6037
• Language: English
• Keywords: Lipids; Cholesterol, HDL; Young Adult; Biological Markers; Aged, 80 and over; Japan; Humans; Mass Screening; Middle Aged; Retrospective Studies; Male; Adult; Female; Hyperlipidemias; Coronary Disease; Cholesterol, LDL; Aged