C-reactive protein (CRP) in the circulation and albumin are recognized indicators of systemic inflammation. In comparison to CRP or albumin alone, a new biomarker called C-reactive protein-to-albumin ratio (CAR) has been proposed to be a more accurate risk predictor for inflammatory diseases. The pathophysiology of pneumonia is characterized by inflammatory processes, although the relationship between CAR and pneumonia has not yet been researched. For a study, researchers sought to evaluate the potential link between CAR and the risk of pneumonia.

In the Kuopio Ischemic Heart Disease research, blood samples from 2,489 males between the ages of 42 and 61 were tested for C-reactive protein and albumin. The Cox regression analysis obtained hazard ratios (HRs) with 95% CIs.

About 598 pneumonia cases were reported over a median follow-up of 26.1 years. The HR (95% CI) for pneumonia comparing the top and bottom thirds of CAR was 1.62 (1.31-2.00) in an analysis that controlled for age, body mass index, smoking status, history of type 2 diabetes, prevalent coronary heart disease, history of asthma, history of chronic bronchitis, history of tuberculosis, alcohol consumption, socioeconomic status, leisure-time physical activity, and total energy intake. For serum CRP, the equivalent adjusted risk was 1.67 (1.34-2.07). There was no proof that serum albumin and the risk of pneumonia were related.

Elevated blood CAR and CRP levels were each linked to an increased risk of pneumonia in middle-aged and older Finnish males. More investigations are required to confirm these results in additional groups and evaluate the potential use of CAR in the prevention and treatment of pneumonia.

Reference: resmedjournal.com/article/S0954-6111(22)00159-7/fulltext