Prevalence of plasma lipid abnormalities and associated risk factors among Iranian adults based on the findings from STEPs survey 2021

Abstract

The study aimed to estimate the prevalence of lipid abnormalities in Iranian adults by demographic characterization, geographical distribution, and associated risk factors using national and sub-national representative samples of the STEPs 2021 survey in Iran. In this population-based household survey, a total of 18,119 individuals aged over 25 years provided blood samples for biochemical analysis. Dyslipidemia was defined by the presence of at least one of the lipid abnormalities of hypertriglyceridemia (≥ 150 mg/dL), hypercholesterolemia (≥ 200 mg/dL), high LDL-C (≥ 130 mg/dL), and low HDL-C (< 50 mg/dL in women, < 40 mg/dL in men), or self-reported use of lipid-lowering medications. Mixed dyslipidemia was characterized as the coexistence of high LDL-C with at least one of the hypertriglyceridemia and low HDL-C. The prevalence of each lipid abnormality was determined by each population strata, and the determinants of abnormal lipid levels were identified using a multiple logistic regression model. The prevalence was 39.7% for hypertriglyceridemia, 21.2% for hypercholesterolemia, 16.4% for high LDL-C, 68.4% for low HDL-C, and 81.0% for dyslipidemia. Hypercholesterolemia and low HDL-C were more prevalent in women, and hypertriglyceridemia was more prevalent in men. The prevalence of dyslipidemia was higher in women (OR = 1.8), obese (OR = 2.8) and overweight (OR = 2.3) persons, those residents in urban areas (OR = 1.1), those with inappropriate physical activity (OR = 1.2), patients with diabetes (OR = 2.7) and hypertension (OR = 1.9), and participants with a history (OR = 1.6) or familial history of CVDs (OR = 1.2). Mixed dyslipidemia prevalence was 13.6% in women and 11.4% in men (P < 0.05). The prevalence of lipid abnormalities was highly heterogeneous among provinces, and East Azarbaijan with 85.3% (81.5-89.1) and Golestan with 68.5% (64.8-72.2) had the highest and lowest prevalence of dyslipidemia, respectively. Although the prevalence of high cholesterol and LDL-C had a descending trend in the 2016-2021 period, the prevalence of dyslipidemia remained unchanged. There are modifiable risk factors associated with dyslipidemia that can be targeted by the primary healthcare system. To modify these risk factors and promote metabolic health in the country, action plans should come to action through a multi-sectoral and collaborative approach.

Figure 1

Map of Age-standardized prevalence of dyslipidemia in 2021 by residual area and sex. The figure shows the age-standardized prevalence of dyslipidemia in different subpopulation categories: (A) females in both rural and urban areas combined (B) males in both rural and urban areas combined (C) both sexes in both areas combined (D) females in urban areas (E) males in urban areas (F) both sexes in urban areas (G) females in rural areas (H) males in rural areas (I) both sexes in rural areas. The color scheme represents quintiles of prevalence, ranging from dark red (highest prevalence) to light yellow (lowest prevalence). The quintile assignment for each map is determined solely based on the data that encompasses the specific subpopulation described by the map. The map was drawn using R. Software version 3.2.1 (http://www.r-project.org, RRID: SCR_001905). WA indicates West Azarbayjan, WE: East Azarbayjan, AR: Ardabil, KD: Kurdistan, ZA: Zanjan, GI: Gilan, KS: Kermanshah, HD: Hamadan, QZ: Qazvin, AL: Alborz, MN: Mazandaran, GO: Golestan, IL: Ilam, LO: Lorestan, MK: Markazi, QM: Qom, TE: Tehran, SM: Semnan, NK: North Khorasan, RK: Khorasan Razavi, KZ: Khuzestan, CM: Chaharmahal and Bakhtiari, KB: Kohkiluye and Bouyerahmad, ES:Isfahan, YA: Yazd, SK: South Khorasan, BS: Boushehr, FA: Fars, KE: Kerman, SB: Sistan and Balouchestan, HG: Hormozgan.

Figure 2

Mean Cholesterol and LDL-C in Iran’s provinces The figure shows the mean (dots) and 95% confidence interval (lines) of (A) female total cholesterol, (B) male total cholesterol, (C) female LDL-C, (D) male LDL-C, in different provinces of the country.