Depresi merupakan kontributor utama beban penyakit global dengan estimasi Disability-Adjusted Life Years (DALYs) mencapai 694,6 per 100.000 penduduk pada tahun 2023. Prevalensi gejala depresi di Indonesia sebesar 1,4% dengan 61% penderita pernah memiliki pikiran untuk mengakhiri hidupnya. Di sisi lain, paparan asap rokok pasif (SHS) pada non-perokok masih sangat tinggi, 74,2% di tempat umum dan 44,8% di tempat kerja, namun hubungannya dengan gejala depresi pada populasi dewasa non-perokok di Indonesia belum banyak diteliti. Penelitian ini bertujuan mengetahui hubungan antara paparan SHS dengan gejala depresi pada orang dewasa non-perokok di Indonesia menggunakan data sekunder SKI 2023 dengan desain cross-sectional. Sampel terdiri dari 353.980 responden dewasa usia 18–59 tahun yang tidak pernah merokok. Gejala depresi diukur menggunakan instrumen MINI ICD-10, sedangkan paparan SHS dikategorikan berdasarkan frekuensi paparan di ruang tertutup. Analisis menggunakan regresi logistik multilevel tiga tingkat dengan penyesuaian bobot survei kompleks. Hasil penelitian menunjukkan sebanyak 67,7% responden terpapar SHS, terdiri dari 21,3% terpapar setiap hari dan 46,4% terpapar tidak setiap hari. Prevalensi gejala depresi sebesar 1,27%, lebih tinggi pada kelompok terpapar SHS setiap hari (1,93%) dibandingkan tidak terpapar (1,09%). Setelah dikontrol seluruh kovariat, paparan SHS setiap hari berhubungan dengan gejala depresi (OR = 1,29; 95% CI: 1,12–1,48), sedangkan paparan tidak setiap hari menunjukkan odds lebih rendah (OR = 0,88; 95% CI: 0,78–0,99). Analisis sensitivitas dengan menggabungkan kategori "tidak terpapar" dan "terpapar tidak setiap hari" sebagai kelompok referensi mengkonfirmasi konsistensi temuan (OR = 1,39; 95% CI: 1,24–1,56), menunjukkan bahwa hubungan antara paparan SHS harian dan gejala depresi bersifat robust. Faktor individu yang berhubungan meliputi penyakit kronis (OR = 2,91; 95% CI: 2,56–3,32), jenis kelamin perempuan (OR = 1,64; 95% CI: 1,37–1,96), tidak bekerja (OR = 1,37; 95% CI: 1,22–1,54), status ekonomi bawah (OR = 1,36; 95% CI: 1,13–1,64), pendidikan rendah (OR = 1,29; 95% CI: 1,14–1,47), dan tidak ada aktivitas fisik (OR = 1,19; 95% CI: 1,05–1,34). Sementara, usia lebih tua berhubungan dengan odds gejala depresi lebih rendah (OR = 0,98; 95% CI: 0,97–0,99), begitupun dengan faktor wilayah, tinggal di pedesaan (OR = 0,77; 95% CI: 0,67–0,88). Nilai Intraclass Correlation Coefficient (ICC) kabupaten/kota sebesar 24,7% mengindikasikan peran konteks wilayah yang masih substansial. Paparan SHS setiap hari terbukti berhubungan dengan gejala depresi pada orang dewasa non-perokok di Indonesia. Temuan ini menegaskan pentingnya penguatan Kawasan Tanpa Rokok (KTR) sebagai strategi pencegahan berbasis kebijakan, integrasi kesehatan mental dalam program pengendalian tembakau, skrining gejala depresi yang diprioritaskan pada kelompok paling rentan dan wilayah dengan KTR lemah, serta perlunya studi lanjut yang bersifat kuasi-eksperimen atau longitudinal.

Depressive symptoms are a major contributor to the global disease burden, with an estimated 694.6 DALYs per 100,000 population in 2023. The prevalence of depressive symptoms in Indonesia is 1.4%, with 61% of those detected having had thoughts of ending their lives, according to the 2023 SKI. Meanwhile, secondhand smoke (SHS) exposure among non-smokers remains high, 74.2% in public places and 44.8% in workplaces; however, its association with depressive symptoms among non-smoking adults in Indonesia has not been extensively studied. This study aims to investigate the association between SHS exposure and depressive symptoms among non-smoking adults in Indonesia using secondary data from the 2023 SKI with a cross-sectional design. The sample consisted of 353,980 adult respondents aged 18–59 years who had never smoked. Depressive symptoms were measured using the MINI ICD-10 instrument, while SHS exposure was categorized based on frequency of exposure in enclosed spaces. Analysis utilized three-level multilevel logistic regression with complex survey weight adjustments. The results showed that 67.7% of respondents were exposed to SHS, consisting of 21.3% exposed daily and 46.4% exposed non-daily. The prevalence of depressive symptoms was 1.27%, higher among those exposed to SHS daily (1.93%) compared to those unexposed (1.09%). After adjusting for all covariates, daily SHS exposure was significantly associated with depressive symptoms (OR = 1.29; 95% CI: 1.12–1.48), whereas non-daily exposure showed lower odds (OR = 0.88; 95% CI: 0.78–0.99). A sensitivity analysis combining the "unexposed" and "non-daily exposed" categories as a single reference group confirmed the consistency of findings (OR = 1.39; 95% CI: 1.24–1.56), demonstrating that the association between daily SHS exposure and depressive symptoms is robust. Individual-level factors associated with depressive symptoms included chronic disease (OR = 2.91; 95% CI: 2.56–3.32), female sex (OR = 1.64; 95% CI: 1.37–1.96), unemployment (OR = 1.37; 95% CI: 1.22–1.54), lower economic status (OR = 1.36; 95% CI: 1.13–1.64), low education (OR = 1.29; 95% CI: 1.14–1.47), and physical inactivity (OR = 1.19; 95% CI: 1.05–1.34), while older age was associated with lower odds of depressive symptoms (OR = 0.98; 95% CI: 0.97–0.99), as well at the area level, residing in rural areas (OR = 0.77; 95% CI: 0.67–0.88). The Intraclass Correlation Coefficient (ICC) at the district/city level of 24.7% indicated a substantial role of area-level context. Daily SHS exposure was significantly associated with depressive symptoms among non-smoking adults in Indonesia. These findings underscore the importance of strengthening smoke-free area policy enforcement as a policy-based prevention strategy for depressive symptoms, integrating mental health into tobacco control programs, prioritizing depressive symptom screening for the most vulnerable groups and areas with weak smoke-free regulations, and the need for further longitudinal or quasi-experimental studies.