Obesity and Smoking Increase Psoriatic Arthritis Activity: DEPAR Study
New evidence: lifestyle factors shape psoriatic arthritis activity
The largest multicenter cohort analysis to date from the Dutch South West Psoriatic Arthritis (DEPAR) registry links modifiable habits — especially obesity and smoking — with higher disease activity in people newly diagnosed with psoriatic arthritis (PsA).
Researchers tracked 938 adults diagnosed with PsA between 2013 and 2023 and found that baseline lifestyle measures were powerful predictors of how active the disease remained after one year (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
What the study looked at
This was a multicenter, prospective cohort study enrolling adults at or near time of PsA diagnosis to examine how everyday behaviors related to disease outcomes during the first year of care (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
The investigators combined standard clinical measures of PsA activity with a simple composite lifestyle score to capture the cumulative effect of several modifiable risk factors at baseline.
Who participated and how common were risk factors?
The cohort included 938 newly diagnosed adults with PsA, enrolled at multiple centers in the southwest Netherlands between 2013 and 2023 (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
At baseline, one-third of participants (33%) met criteria for obesity, and more than half (51%) had abdominal obesity, highlighting a high burden of excess weight in early PsA (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Current smoking was reported by 19% of the group, while alcohol use was common (72% reported drinking). Only a small share (about 3%) were classified as physically inactive, though this may be influenced by self-report (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Compared with the general Dutch population, the study population had higher rates of obesity and heavier alcohol use, while smoking prevalence was similar to national averages (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
How the researchers summarized lifestyle risk
To measure combined lifestyle burden, investigators created a composite lifestyle risk score ranging from 0 to 5, where higher numbers indicate more risk factors present at baseline (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
The score counted five binary factors: abnormal body mass index (BMI), abdominal obesity, current smoking, no alcohol consumption, and physical inactivity — each scored as 0 or 1 and summed into the overall risk value (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Link between lifestyle score and disease activity
A clear pattern emerged: higher lifestyle risk scores at diagnosis were consistently associated with greater PsA activity at one year, even after adjusting for other variables (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Specifically, each step up in the lifestyle score was associated with higher values on both the PASDAS (PsA Disease Activity Score) and DAPSA (Disease Activity in Psoriatic Arthritis) measures, two commonly used composite disease-activity indices (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Patients with more lifestyle risk factors also had lower odds of reaching important treatment goals: they were less likely to achieve low disease activity (LDA) by PASDAS or DAPSA criteria and less likely to reach minimal disease activity (MDA) (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Which behaviors mattered most?
When the team examined each lifestyle component separately, obesity (both general and abdominal) and current smoking emerged as the main drivers of worse outcomes (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Both forms of obesity were independently associated with higher disease-activity scores and reduced likelihood of achieving LDA and MDA, suggesting that excess fat — especially abdominal fat — contributes meaningfully to persistent inflammation (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Current smokers — particularly those with moderate-to-heavy use — had higher PASDAS and DAPSA scores and were less likely to achieve treatment targets compared with non-smokers, while former and light smokers did not show the same strong associations (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Biologic reasons behind the links
Obesity promotes a chronic, low-grade inflammatory state through increased release of pro-inflammatory cytokines and adipokines from fat tissue, which can amplify joint and skin inflammation seen in PsA (Source: Frontiers in Immunology, Nedunchezhiyan et al., 2022).
Similarly, cigarette smoke activates multiple inflammatory pathways and can increase oxidative stress and pain sensitivity, mechanisms that plausibly worsen disease activity and undermine treatment response in inflammatory arthritis (Source: Respiratory Physiology & Neurobiology, Rom et al., 2013).
Alcohol and physical activity: more complex signals
Unlike obesity and smoking, neither alcohol consumption nor physical activity showed a reliable independent association with PsA activity after the researchers adjusted for confounders (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Some links appeared in unadjusted analyses, but these associations disappeared in multivariable models, suggesting that the relationship between alcohol and disease is complex and potentially bidirectional — for example, people with worse disease might change drinking habits as a result of symptoms or treatment (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
The very low rate of physical inactivity in this cohort limited the ability to detect an effect of sedentary behavior; the authors also cautioned that self-reported activity levels may overestimate true physical activity (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
What this means for patients and clinicians
The study supports a more holistic approach to PsA care where modifiable behaviors are assessed at diagnosis to flag patients at higher risk for persistent disease activity (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
While medications remain central to controlling PsA, these findings strengthen the argument for integrating targeted lifestyle interventions — especially weight management and smoking cessation — into routine clinical pathways to improve outcomes.
Practical steps clinicians can consider include early weight-loss counseling or referral to a registered dietitian, structured exercise programs tailored for joint health, referral to smoking-cessation services, and coordinated care with behavioral health when needed to support long-term change.
What researchers want to see next
The authors emphasize the need for longitudinal studies and interventional trials that test whether deliberate changes in weight and smoking behavior improve PsA outcomes over time and whether combining lifestyle programs with drug therapy yields better long-term disease control (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
Other important questions include identifying which types of weight-loss interventions (dietary, pharmacologic, or bariatric) and which smoking-cessation approaches are most effective specifically for people with PsA, as well as how to implement these interventions equitably in real-world clinical settings.
Bottom line
Data from nearly 1,000 people in the DEPAR registry show that a greater burden of modifiable lifestyle risk factors — chiefly obesity and current smoking — is associated with worse PsA activity and a lower chance of achieving common treatment targets after one year (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
These findings do not replace the need for effective pharmacologic care, but they do point to clear, actionable opportunities to improve outcomes by addressing weight and smoking early in the course of disease.
Sources
- Hojeij B, Tchetverikov I, Kok MR, et al. Associations of lifestyle-related factors and psoriatic arthritis disease activity: the Dutch South West Psoriatic Arthritis study. Arthritis Care & Research (Hoboken). Published online May 4, 2026. doi:10.1002/acr.80080 (Source: DEPAR registry study, Hojeij et al., Arthritis Care Res).
- Nedunchezhiyan U, Varughese I, Sun AR, Wu X, Crawford R, Prasadam I. Obesity, Inflammation, and Immune System in Osteoarthritis. Frontiers in Immunology. Published July 4, 2022. doi:10.3389/fimmu.2022.907750 (Source: Frontiers in Immunology, Nedunchezhiyan et al., 2022).
- Rom O, Avezov K, Aizenbud D, Reznick AZ. Cigarette smoking and inflammation revisited. Respiratory Physiology & Neurobiology. (Source: Respiratory Physiology & Neurobiology, Rom et al., 2013).