Introduction. The study of cytokine profile features in individuals of different age categories with age-associated diseases (AAD) identified at an early stage may have practical significance in the field of early diagnostics of diseases for timely correction of health status by prescribing appropriate therapy. Interleukin-6 has some features of hormones and has a pleiotropic effect, which determines the importance of further more detailed study of the features of this biologically active substance in the context of the sequence of AAD manifestation. The purpose of the study – to study the concentration of interleukin-6 (molecular level) and the severity of geriatric syndromes (organismal level) in individuals with a newly diagnosed АAD (using the example of diseases characterized by high blood pressure, type 2 diabetes mellitus and senile cataracts). Materials and methods. A total of 335 people were included in the study, including 115 people with a diagnosis (according to ICD-10) I10-I15 (diseases characterized by high blood pressure (DHBP)), 110 people with a diagnosis of E11 (non-insulin-dependent diabetes mellitus, type 2 diabetes mellitus (T2DM)) and H25 (senile cataract (SC)), hospitalized in St. Petersburg State Budgetary Healthcare Institution City Multi-field Hospital №2 from 09/01/2023 to 11/01/2023. The study was conducted in two stages: at the first stage, the presence and severity of geriatric syndromes (senile asthenia, sarcopenia) was assessed using validated questionnaires (FRAIL, SARC-F), the second stage included a study of the concentration of interleukin-6 (IL-6) in the blood serum. Results. The results of the work revealed preasthenia in people with DHBP, T2DM, asthenia in people with SC. Sarcopenia was absent in the group of people with DHBP, T2DM, but it was present in people with SC. In the group of people suffering from DHBP, the median age was 61 years, in people with T2DM - 65 years, with SC - 75 years. The highest concentration of interleukin-6 in the blood was in the group of people with SC, the lowest - in people suffering from DHBP. In people with T2DM, the level of the cytokine in the blood occupied an intermediate position between the other AAD. Discussion. There is reason to believe that at a certain concentration of interleukin-6 in the blood, at a certain age, DHBP first begins to manifest (more often in middle-aged people), followed by T2DM (in elderly people), and then SC (in old people), thereby confirming the sequence of manifestation of AAD. Undoubtedly, as AAD accumulates in a person, the severity of geriatric syndromes increases. Conclusion. The presence of the order of the most frequent occurrence of AAD in people of a specific age category in the following sequence was revealed: DHBP, T2DM, SC. As age increases, the level of interleukin-6 in the blood increases, the severity of geriatric syndromes (senile asthenia, sarcopenia) increases.