Malnutrition Linked to All-Cause Mortality in Patients with Rheumatoid Arthritis

Malnutrition, which is prevalent in patients with rheumatoid arthritis (RA), was strongly associated with an increased risk of all-cause mortality, according to a study published in Frontiers in Nutrition.¹

“Malnutrition has been shown to affect quality of life in chronically ill elderly populations,” investigators noted. “Disease-related malnutrition is strongly associated with morbidity, disability, short- and long-term mortality, and impaired disease recovery. Patients with RA are vulnerable to malnutrition. A previous study shows that about two-thirds of RA patients have malnutrition. The high incidence of malnutrition in RA patients may be related to the inflammatory response during the disease, metabolic abnormalities, and disuse atrophy due to activity restriction.”

A total of 1976 adult patients (59.9% female, 69.9% non-Hispanic White, with a mean age of 57.38 years) with RA were evaluated using the National Health and Nutrition Examination Survey (NHANES), a nationally representative health survey conducted by the National Center for Health Statistics (NCHS), between 1999 and 2014. The primary outcome was all-cause mortality. The Controlled Nutritional Status Score (CONUT) and Nutritional Risk Index (NRI) determined the nutritional status of the patient population while the Kaplan-Meier (KM) survival curves Cox proportional hazards regression models analyzed associations between malnutrition and all-cause mortality.

At baseline, 57.5% (n = 1258) patients had hypertension, 32.3% (n = 775) had diabetes mellitus (DM), 15.8% (n = 285) had cancer, 8.8% (n = 184) had congestive heart failure (CHF), and 8.4% (n = 1717) had coronary heart disease (CHD).

The percentage of patients with malnutrition, which was observed in 18.8% via CONUT and 26.6% using NRI, which emphasizes the importance of attention and innervation in the nutritional status of this patient population. Mild malnutrition was reported in 18.3% (n = 391) patients using CONUT criteria and 15.6% (n = 204) using NRI criteria, while 0.4% and 11.0% had moderate-to-severe malnutrition, respectively.

The KM survival curves indicated that malnutrition was linked to a higher incidence of all-cause mortality during a 10-year follow-up period (log-rank test, P < 0.001). The adjusting hazard ratio (aHR) for all-cause mortality in patients with moderate-to-severe malnutrition for CONUT was 5.63 (95% CI, 2.55–12.45; P < 0.001) and 2.56 for NRI (95% CI, 1.81–3.62; P < 0.001) when compared with patients without malnutrition in a fully corrected model.

A subgroup analysis of CONUT score reported that the female population had a higher risk of all-cause mortality when compared with the male patients with RA (aHR, 2.04; 95% CI, 1.27–3.28; P = 0.003 and aHR, 1.28; 95% CI, 0.73–2.26; P = 0.394, respectively). However, in the NRI score analysis, the malnourished male population had a higher risk when compared with female patients (aHR, 2.81; 95% CI, 1.74–4.56; P < 0.001 and aHR, 2.36; 95% CI, 1.72–3.24; P < 0.001, respectively).

The retrospective study design may have hindered timeliness. Additionally, objectivity and accuracy of nutritional status may have been biased due to lack of a comparison cohort. Lastly, investigators did not evaluated changes in nutritional status over time.

“Malnutrition assessment allows clinicians to determine the high risk of mortality in patients with RA,” investigators concluded. “Adequate assessment of nutritional status and necessary nutritional guidance can help improve the prognosis of patients with RA. Further clinical trials are needed to prospectively assess the effect of nutritional interventions on the prognosis of patients with RA.”

Reference:

Tian P, Xiong J, Wu W, et al. Impact of the malnutrition on mortality in Rheumatoid arthritis patients: A cohort study from NHANES 1999-2014. Front Nutr. 2023;9:993061. Published 2023 Jan 4. doi:10.3389/fnut.2022.993061