The role of cognitive complaints has recently received increasing attention in dementia research.

To investigate whether the subjective perception of cognitive deficits is related to multi-morbidity in an old Italian cohort.

The study population(N = 6,825) included persons who did not receive a diagnosis of dementia(DSM-IIIR criteria), were not cognitively impaired and scored < 4 at the Global Deterioration Scale(GDS). On GDS stage one, Individuals with GDS score equal to one do not report memory problems and no deficits are detected during the interview. In subjects with GDS score = 2, a very mild cognitive decline is appreciable. On GDS score = 3,deficiencies begin to be noted. The examining physicians diagnosed the somatic disorders according to the International Classification Disease version 10 (ICD-10). Mental health was clinically assessed by the examining physicians with semi-structured questions. A multimorbidity index was created based on the number of co-occurring chronic disorders. Binary logistic regression analyses were used to estimate multiadjusted Odds ratio (aOR) and 95% Confidence Intervals (CI).

According to GDS, 28.4% (N = 1,940) of participants reported some degree of perceived cognitive decline. Cognitive complaints were associated with increasing age, low education, and multimorbidity. Stroke (aOR,95%CI 1.6;1.3–1.9),diabetes(aOR,95%CI 1.4;1.1–1.7),depressive(aOR,95%CI 2.2;1.8–2.7) and anxiety symptoms(aOR, 95%CI 1.5;1.3–1.8) were significantly associated with perceived cognitive decline. When performances at MMSE were taken into account, cardiovascular(aOR,95%CI 2.3;1.3–4.1) and respiratory diseases(aOR,95%CI 1.9;1.0–3.6) were associated with self-perceived cognitive decline in absence of observable cognitive deficits.

Cognitive complaints have many somatic correlates and some of them may account for the discrepancy between perceived cognitive decline and cognitive assessment.