Undiagnosed Diabetes and Insulin Resistance Hidden Behind Self‑Report in Libyan Adults

Abstract

Background: Self‑reported diabetes status is commonly used in epidemiologic surveys but may misclassify glycaemic status and metabolic risk.

Objective: To evaluate agreement between pre‑test self‑reported diabetes status and laboratory‑confirmed HbA1c and insulin resistance (IR) classifications in a Libyan adult sample.

Methods: Cross‑sectional secondary analysis of N = 223 adults enrolled in a HOMA‑IR cutoff study in Zletin, Libya. Participants answered a pre‑specimen questionnaire item (“Do you have diabetes?”: Yes / No / Don’t know) and provided blood for HbA1c and biochemical IR classification (HOMA‑IR–based categories). HbA1c was categorized as Normal (<5.7%), Prediabetic (5.7–6.4%), and Diabetic (≥6.5%). Cross‑tabulations, Pearson chi‑square, and Spearman rank‑order correlation were used to examine associations; significance set at p < 0.05.

Results: Self‑report: 20.6% Yes, 76.7% No, 2.7% Don’t know. HbA1c classification: 50.7% Normal, 26.5% Prediabetic, 22.9% Diabetic. Cross‑tabulation showed 84.8% of self‑reported diabetics had diabetic‑range HbA1c; 4.1% of those denying diabetes had diabetic‑range HbA1c; 83.3% of “Don’t know” respondents were diabetic by HbA1c. High IR was present in 73.9% of self‑reported diabetics and 46.8% of those denying diabetes. Pearson chi‑square indicated a significant association between self‑report and IR levels (χ² = 18.861, df = 6, p = 0.004). Spearman correlation showed a marginal negative association (ρ = −0.131, p = 0.051).

Conclusions: Self‑report aligns with biochemical markers for most diagnosed individuals, but a meaningful minority—especially those denying or unsure of diabetes—had undiagnosed diabetes or elevated IR. Some self‑reported diabetics with normal HbA1c likely reflect well‑controlled disease. Routine biochemical screening and targeted risk assessment are recommended.