A systematic review and meta-analysis of the prevalence of dyslipidaemia among adults in Malaysia

Dyslipidaemia is an established cardiovascular risk factor. This study aimed to determine the pooled prevalence of dyslipidaemia in Malaysian adults. A systematic review and meta-analysis of all cross-sectional, longitudinal observational studies which reported the prevalence of elevated total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), triglycerides (TG), and reduced high-density lipoprotein cholesterol (HDL-c) in adults 18 years old and older, was conducted. A comprehensive search of PubMed and Cochrane Central Register of Controlled Trials (which included Medline, EMBASE and major trial registers) from inception to October 18, 2022, was performed. Risk-of-bias was evaluated using the Johanna-Briggs Institute Prevalence Critical Appraisal Tool, while certainty of evidence was assessed using an adapted version of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Random-effects meta-analyses were performed using MetaXL. This report follows the PRISMA reporting guidelines. The protocol was registered with PROSPERO (CRD42020200281). 26 556 studies were retrieved and 7 941 were shortlisted initially. From this, 70 Malaysian studies plus two studies from citation searching were shortlisted; 46 were excluded, and 26 were included in the review (n = 50 001). The pooled prevalence of elevated TC (≥ 5.2 mmol/L), elevated LDL-c (≥ 2.6 mmol/L), elevated TG (≥ 1.7 mmol/L), and low HDL-c (< 1.0 mmol/L in men and < 1.3 mmol/L in women) were 53% (95% CI 39–67%, I2 = 100%), 73% (95% CI 50–92%, I2 = 100%), 36% (95% CI 32–40%, I2 = 96%), and 40% (95% CI 25–55%, I2 = 99%), respectively. This review found that the prevalence of all dyslipidaemia subtypes is high in Malaysian adults. Ongoing efforts to reduce cardiovascular diseases in Malaysia should integrate effective detection and treatment of dyslipidaemia.

10b List and define all other variables for which data were sought (e.g.participant and intervention characteristics, funding sources).Describe any assumptions made about any missing or unclear information.
Study risk of bias assessment 11 Specify the methods used to assess risk of bias in the included studies, including details of the tool(s) used, how many reviewers assessed each study and whether they worked independently, and if applicable, details of automation tools used in the process.

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Effect measures 12 Specify for each outcome the effect measure(s) (e.g.risk ratio, mean difference) used in the synthesis or presentation of results.6 Synthesis methods 13a Describe the processes used to decide which studies were eligible for each synthesis (e.g.tabulating the study intervention characteristics and comparing against the planned groups for each synthesis (item #5)).

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13b Describe any methods required to prepare the data for presentation or synthesis, such as handling of missing summary statistics, or data conversions.

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13c Describe any methods used to tabulate or visually display results of individual studies and syntheses.6 13d Describe any methods used to synthesize results and provide a rationale for the choice(s).If meta-analysis was performed, describe the model(s), method(s) to identify the presence and extent of statistical heterogeneity, and software package(s) used.

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13e Describe any methods used to explore possible causes of heterogeneity among study results (e.g.subgroup analysis, meta-regression).6 13f Describe any sensitivity analyses conducted to assess robustness of the synthesized results.7 Reporting bias assessment 14 Describe any methods used to assess risk of bias due to missing results in a synthesis (arising from reporting biases).

# Checklist item
Location where item is reported Certainty assessment 15 Describe any methods used to assess certainty (or confidence) in the body of evidence for an outcome.6

Study selection 16a
Describe the results of the search and selection process, from the number of records identified in the search to the number of studies included in the review, ideally using a flow diagram.

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16b Cite studies that might appear to meet the inclusion criteria, but which were excluded, and explain why they were excluded.

eFigure 7 .eFigure 8 .
Doi plot and LFK index for Elevated Triglycerides Random effects by Setting LFK index: -0.83 (No asymmetry) Doi plot and LFK index for Low HDL-c Random effects by Setting LFK index: 1.12 (Minor asymmetry)

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist
Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al.The PRISMA 2020 statement: an updated guideline for reporting systematic reviews.BMJ 2021;372:n71.doi:10.1136/bmj.n71Formore information, visit: http://www.prisma-statement.org/ 19 For all outcomes, present, for each study: (a) summary statistics for each group (where appropriate) and (b) an effect estimate and its precision (e.g.confidence/credible interval), ideally using structured tables or plots.20aForeachsynthesis,brieflysummarise the characteristics and risk of bias among contributing studies.9,1020bPresentresults of all statistical syntheses conducted.If meta-analysis was done, present for each the summary estimate and its precision (e.26 Declare any competing interests of review authors.16Availability of 27 Report which of the following are publicly available and where they can be found: template data collection forms; data extracted from included PRISMA 2020 Checklist studies; data used for all analyses; analytic code; any other materials used in the review.eTable1.From:

GRADE assessment of the studies included in meta-analyses
assessed using the JBI Critical Appraisal Checklist for Studies Reporting Prevalence Data ranged from low to high risk of bias.Only 6 studies included in this meta-analysis were judged as having high risk of bias.† Based on significant heterogeneity (I 2 ranged from 90 to 100%).‡ Indirectness -The study population can be generalized to the population of interest.§ Only very few studies had large 95% CIs.¶ Doi plots and LFK indices were consistent with the presence of publication bias.
* Study quality

Sensitivity analysis -Forest Plot Showing Prevalence of Low HDL-cholesterol (HDL-c <1 in men & <1.3 women) in Community-based Studies and Hospital or Clinic-based Studies Excluding Studies with High Risk of Bias (Mohd Zainuddin LR 2011)
Doi plot and LFK index for Elevated Total Cholesterol Doi plot and LFK index for Elevated LDL-Cholesterol