Neuroticism, extraversion, stressful life events and asthma: a cohort study of middle-aged adults

Background:  Stressful life events can trigger asthma exacerbations, but could also contribute to the development of incident asthma. However, only few studies have investigated the association between stressful life events and adult asthma prospectively. Likewise, stress-related personality traits (e.g. neuroticism and extraversion) may increase asthma risk, but this has been examined in only one prospective study. We therefore aimed to investigate the association between neuroticism, extraversion, stressful life events and incident asthma.
Methods:  A population-based sample of 5114 middle-aged adults completed questionnaires between 1992 and 1995. Among those alive in 2002/2003, 4010 (83%) were followed-up by questionnaires. Exposures of interest included neuroticism, extraversion and three stressful life events (unemployment, having broken off a life partnership and death of a close person). Associations with incident asthma were estimated by multivariable risk ratios (RR) and 95% confidence intervals (95% CI) using Poisson regression.
Results:  High vs low neuroticism predisposed to developing asthma (RR = 3.07, 95% CI = 1.71–5.48), but high extraversion did not (RR = 1.30, 95% CI = 0.79–2.15). Having broken off a life partnership significantly increased asthma risk (RR = 2.24, 95% CI = 1.20–4.21) in contrast to death of a close person (RR = 1.06, 95% CI = 0.64–1.75) or unemployment (RR = 1.65, 95% CI = 0.72–3.78).
Conclusions:  High levels of neuroticism may increase the risk of asthma in middle-aged adults. Having broken off a life partnership was the only stressful event, which was associated with incident asthma. Synthesized with evidence from earlier studies, this could reflect that interpersonal conflicts may increase asthma risk, possibly along an immunological pathway.     

Estrogen receptor status in CHEK2-positive breast cancers: implications for chemoprevention

To investigate the relationship between CHEK2 mutation status and estrogen receptor (ER) status in unselected cases of early-onset breast cancer from Poland, we screened 4441 women diagnosed with breast cancer younger than 51 years and 7217 controls for three inherited mutations in CHEK2 (1100delC, IVS2+1G>A, del5395). ER status was compared between CHEK2 -positive and CHEK2 -negative breast cancer cases. A truncating mutation in CHEK2 was seen in 140 of 4441 cases and in 70 of 7217 controls [odds ratio (OR) = 3.3; 95% CI = 2.5–4.4; p < 0.0001]. ER status was available for 92 of 140 mutation carriers and for 3001 of 4301 non-carriers with breast cancer. The OR was higher for ER-positive cancers (OR = 3.9; 95% CI = 2.7–5.4; p < 0.0001) than for ER-negative cancers (OR = 2.1; 95% CI = 1.3–3.3; p = 0.002). Sixty-six of the 92 breast cancers in carriers of CHEK2 truncating mutations were ER positive compared with 1742 of the 3001 breast cancers in non-carriers (72% vs 58%; p = 0.01). Women with a CHEK2 mutation face a fourfold increase in the risk of ER-positive breast cancer and might be candidates for tamoxifen chemoprevention.     

Analysis of CD28 and CTLA-4 gene polymorphisms in Turkish patients with Behcet's disease

In this study we aimed to investigate IVS3 +17T/C single nucleotide polymorphism (SNP) of CD28 gene, +49A/G and ?318C/T SNPs of CTLA‐4 gene in patients with Behçet's disease (BD) and their potential association to the main clinical features of the disease. These polymorphisms were investigated in a Turkish population of 123 patients with BD and 179 healthy controls, by using PCR‐RFLP technique. HLA‐B*51 genotype was also studied in both groups by using PCR‐SSP. The frequency of IVS3 +17TC genotype of the CD28 gene was significantly increased in BD patients compared to controls (43.6% vs. 31.2%, OR = 1.663, 95% CI = 1.033–2.679, P = 0.039). CTLA‐4 +49GG genotype frequency was found to be significantly lower in patients with BD than those of healthy controls (4% vs. 10.6%, OR = 0.357, 95% CI = 0.130–0.983, P = 0.05). Genotype and allele frequencies of the CTLA‐4–318C/T polymorphism between the BD and healthy control groups were not significantly different (12.2% vs. 10.6%, OR = 1.170, 95% CI = 0.570–2.402, P = 0.713). There were no associations between the studied polymorphisms and the main clinical features of BD. The frequencies of HLA‐B*51 were 60.3% and 30.7% in BD and control groups, respectively (OR = 3.429, 95% CI = 2.115–5.559, P = 0.0001). Association between HLA‐B*51 and each studied polymorphism did not reach to significant levels (OR = 0.479, 95% CI = 0.228–1.004, P = 0.064 for CD28 IVS3 +17TT genotype; OR = 2.180, 95% CI = 1.025–4.639, P = 0.061 for TC genotype; OR = 1.570, 95% CI = 0.870–2.836, P = 0.146 for C allele). These results may suggest that CD28 IVS3 +17TC genotype may be a risk factor for the development of BD, on the contrary CTLA‐4 +49GG genotype may be protective in the studied Turkish population.     

Association of 677C>T polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene with bipolar disorder and schizophrenia

Methylenetetrahydrofolate reductase (MTHFR) gene polymorphism 677C>T has been shown to be a risk factor for psychiatric disorders. We investigated the genotype and allelic frequencies of MTHFR 677C>T polymorphism in the group of patients with bipolar disorder type I (BDI) (n = 200) and schizophrenia (n = 200), and in the control group (n = 300). Odds ratio (OR) for patients with BD and schizophrenia with 677T allele was 1.988 ((95% CI = 1.370–2.883); P = 0.0003 (P = 0.0006 after Bonferroni correction)) and 1.796 ((95% CI = 1.237–2.609); P = 0.0020 (P = 0.0040 after Bonferroni correction)), respectively. The stratification of patients based on gender revealed significant association of 677T allele with male patients with BDI and schizophrenia (OR = 2.393; 95% CI = 1.429–4.006; P = 0.0008 and OR = 2.036; 95% CI = 1.207–3.433; P = 0.0073, respectively). This finding indicates possible association of BD and schizophrenia with the 1p36.3 MTHFR locus.     

Common polymorphisms in the MDM2 and TP53 genes and the relationship between TP53 mutations and patient outcomes in glioblastomas

MDM2 SNP309 is associated with younger age of tumor onset in patients with Li-Fraumeni syndrome, and TP53 codon 72 polymorphism decreases its apoptotic potential. Glioblastomas frequently show genetic alterations in the TP53 pathway. In the present study, we assessed MDM2 SNP309 in 360 glioblastomas, and correlated these with patient age and survival, as well as other alterations in the TP53 pathway. Frequencies of the MDM2 SNP309 T/T, T/G and G/G genotypes in glioblastomas were 40%, 46% and 14%, respectively. Multivariate analysis showed that MDM2 SNP309 G/G allele was significantly associated with favorable outcome in female glioblastoma patients (hazard ratio 0.54; 95% CI = 0.32–0.92). There was a significant association between MDM2 SNP309 G alleles and TP53 codon 72 Pro/Pro in glioblastomas. Glioblastoma patients with TP53 codon 72 Pro/Pro genotype were significantly younger than Arg/Arg carriers (mean 50.2 vs. 56.1 years; P  = 0.018). Multivariate analysis showed that those with TP53 codon 72 Arg/Pro allele had significantly shorter survival than those with Arg/Arg allele (hazard ratio 1.35; 95% CI = 1.07–1.71). Detailed analyses revealed that TP53 codon 72 Pro allele was significantly associated with shorter survival among patients with glioblastomas carrying a TP53 mutation, and among those treated with surgery plus radiotherapy.     

CTLA4 gene polymorphisms and soluble CTLA4 protein in Behcet's disease

Cytotoxic T lymphocyte antigen 4 (CTLA4; CD152) is a costimulatory molecule expressed on activated T cells that plays a key inhibitory role during T lymphocyte activation. The gene encoding for CTLA4 has been suggested as a candidate for conferring susceptibility to autoinflammatory diseases. We investigated the polymorphisms of the CTLA4 gene [promoter region (−1722 T/C, −1661 A/G and −318 C/T) and exon 1 (+49 G/A)] and the differences of serum soluble sCTLA4 levels in 285 patients with Behcet's disease (BD) and 287 controls. The frequency of the CTLA4 −1661 GG genotype was significantly higher in BD patients than in controls [ P  = 0.019, odds ratio (OR) = 5.2, 95% confidence interval (CI) = 1.13–23.86]. Also, the genotype frequency for CTLA4 −1722 TC was significantly higher ( P  = 0.014, OR = 1.8, 95% CI = 1.13–2.99), while CTLA4 −1722 CC was significantly lower ( P  = 0.018, OR = 0.4, 95% CI = 0.20–0.87) in BD patients with ocular lesions compared with patients without this symptom. Serum sCTLA4 levels in BD patients were significantly lower, especially in BD patients with the CTLA4 +49 G allele, than those in healthy controls ( P  < 0.05). Although our understanding of the role of the CTLA4 gene and its protein product in BD is incomplete, these results suggest that single nucleotide polymorphisms of the promoter and exon regions in the CTLA4 gene are candidates that predispose to BD and that sCTLA4 may be related to the immunological abnormalities and disease expressions associated with BD.     

Healthcare Interventions for Perinatal Depression in Socially Disadvantaged Women: A Systematic Review and Meta‐Analysis

The aim of this systematic review was to identify, characterize, and analyze the effectiveness of healthcare interventions for perinatal depression in socially disadvantaged women. Prominent biomedical databases were searched in April 2013. Sixteen articles assessing 15 interventions to decrease depressive symptoms in socially disadvantaged women were selected. Most interventions were carried out in the United States (n = 11) and targeted ethnic minorities (n = 9). Approximately half of the interventions (53%) were effective in decreasing depressive symptoms, observing that culturally adapted, interpersonal therapy interventions were the most effective. Eleven interventions were included in the meta‐analysis that showed a statistically significant reduction in overall depressive symptoms (?0.44, 95% CI [?0.67, ?0.22]). Meta‐regression indicated that several characteristics increased the effectiveness of the interventions.     

Association of PTPN22 gene functional variants with development of pulmonary tuberculosis in Moroccan population

Mycobacterium tuberculosis , the causal agent of pulmonary tuberculosis (TB), remains a major health problem throughout the world causing high mortality in humans. Previous studies showed that several genes may play crucial roles in susceptibility to TB. The PTPN22 gene encodes the lymphoid tyrosine phosphatase that has an important regulatory effect on T- and B-cell activation in immune response. The purpose of this study was to investigate the role of two functional missense single nucleotide polymorphisms (SNPs) of the PTPN22 gene region (R620W and R263Q) in the susceptibility to TB in the Moroccan population. A case–control association study was performed including 123 pulmonary TB patients and 155 healthy controls. All subjects were genotyped by TaqMan SNP genotyping assays. Regarding the PTPN22 R620W (C1858T) SNP, we observed a statistically significant difference in the distribution of the PTPN22 1885T allele between pulmonary TB patients and healthy controls (0.41% vs 3.2%, P  = 0.01, odds ratio (OR) = 0.14, 95% confidence interval (CI) = 0.01–0.93). With respect to the PTPN22 R263Q (G788A), we observed an increase of 788A allele frequencies in TB patients compared with those in healthy controls (3.65% vs 0.65%, P  = 0.01, OR = 5.85, 95% CI = 1.17–39.55). These results suggest that PTPN22 gene variants may affect susceptibility to TB in the Moroccan population.     

Secular changes in incidence and mortality associated with Staphylococcus aureus bacteraemia in Quebec, Canada, 1991–2005

In order to examine secular changes in the incidence and mortality associated with Staphylococcus aureus bacteraemia before and after the emergence of methicillin-resistant S. aureus (MRSA), a retrospective cohort study of 815 patients with S. aureus bacteraemia was performed in the Estrie region of Quebec, Canada, between 1991 and 2005. The primary outcome was all-cause 30-day mortality. Between 1991–1993 and 2003–2005, the proportion of cases attributed to endocarditis and pneumonia increased from 4% to 11% and from 2% to 11%, respectively, while that attributed to catheter infections decreased from 49% to 17%. MRSA was almost absent in 1991–1999, but accounted for 10% and 20% of cases in 2000–2002 and 2003–2005, respectively. The population incidence of bacteraemia caused by methicillin-susceptible S. aureus (MSSA) remained stable between 1997 and 2005, while that of MRSA increased from 0 to 7.4/100 000. Risk-factors for mortality included age, co-morbidities, female gender, residence outside the city of Sherbrooke, pneumonia (OR 3.35, 95% CI 1.96–5.73) or endocarditis (OR 2.89, 95% CI 1.67–5.01) as the source, and an absence of treatment. After adjusting for confounders, patients with MRSA bacteraemia had a higher mortality rate than those with MSSA bacteraemia (OR 2.21, 95% CI 0.99–4.96, p 0.053). Mortality in patients with MSSA bacteraemia was 19% (16/83) in 1991–1993, 23% (26/113) in 1994–1996, 29% (50/173) in 1997–1999, and 28% (52/185) in 2000–2002, decreasing to 15% (28/192) in 2003–2005, which impacted on the relative mortality rates of MRSA and MSSA. MRSA did not replace, but added to, an existing stable incidence of MSSA bacteraemia.     

The CD226 gene in susceptibility of type 1 diabetes

The rs763361 single nucleotide polymorphism (SNP) within the CD226 gene has recently been reported as a novel susceptible locus for type 1 diabetes. The CD226 gene is implicated in the regulation of a number of cells involved in immune mechanisms leading to β-cell destruction in type 1 diabetes. The aim of the present study was to confirm the association of the CD226 gene with type 1 diabetes in Estonian population. The TT genotype [odds ratio (OR) = 2.29, 95% confidence interval (CI) = 1.25–4.18, P  = 0.0071) and the T allele (OR = 1.48, 95% CI = 1.11–1.98, P  = 0.0084) of the rs763361 SNP were associated with the risk of type 1 diabetes. The current study replicates the novel association of the rs763361 SNP in susceptibility of type 1 diabetes and supports the CD226 gene as a susceptible candidate locus for type 1 diabetes outside the major histocompatibility complex region.     

The CD3Z 844 T>A polymorphism within the 3'-UTR of CD3Z confers increased risk of incidence of systemic lupus erythematosus

Recently, a family-based association analysis showed that the haplotype carrying a low expression of the variant CD3Z 844 T>A (rs1052231) polymorphism located in the 3'-untranslated region of CD3Z predisposes to systemic lupus erythematosus (SLE) incidence. We analyzed the prevalence of the CD3Z 844 T>A polymorphism in SLE patients ( n  = 152) and controls ( n  = 304) in Poland. We observed that women with the CD3Z AA and CD3Z AT genotypes exhibited a 1.845-fold increased risk of SLE [95% confidence intervals (95% CI) = 1.222–2.787, P  = 0.0038]. However, we did not find an increased risk for the homozygous CD3Z AA genotype (odds ratio = 1.204, 95% CI = 0.2838–5.108, P  = 1.0000). This observation confers that genetic factors causing a decreased level of CD3-ζ in T cells may predispose to SLE incidence.     

CTLA-4 +49A/G polymorphism is associated with Behçet's disease in a Tunisian population

The involvement of excessive T-helper cell functions in the pathogenesis of Behçet's disease (BD) has been reported. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) plays a role in T-cell downregulation. In this report, we investigated the possible association between BD patients and the CTLA-4 +49A/G polymorphism in Tunisian population. A total of 135 Tunisian BD patients and 151 healthy blood donors from the same geographic area were genotyped by polymerase chain reaction for the CTLA-4 +49 A/G polymorphism. A highly significant difference between Tunisian BD patients and healthy controls was found regarding the distribution of CTLA-4 +49 A allele [ P  < 10⁻⁷; χ² = 75.63; odds ratio (OR) = 4.63; 95% confidence interval (CI) = 3.20–6.72] and genotype frequencies ( P  < 10⁻⁷; χ² = 71.02). Furthermore, in the BD group, the A allele was predominant in males (76.3%) when compared with females (62%), ( P  = 0.014; χ² = 5.97; OR = 1.99; 95% CI = 1.10–3.59). No relationship was found between the studied genotype and clinical manifestations. Our results show a gene dose effect of the A allele on the BD. The A allele exerts a stronger effect on disease susceptibility in males compared with females.     

The socio-economic burden of asthma is substantial in Europe

Background:  Few data are available on the asthma burden in the general population. We evaluated the level and the factors associated with the asthma burden in Europe.
Methods:  In 1999–2002, 1152 adult asthmatics were identified in the European Community Respiratory Health Survey (ECRHS)-II and the socio-economic burden (reduced activity days and hospital services utilization in the past 12 months) was assessed.
Results:  The asthmatics with a light burden (only a few reduced activity days) were 13.2% (95% CI: 11.4–15.3%), whereas those with a heavy burden (many reduced activity days and/or hospital services utilization) were 14.0% (95% CI: 12.1–16.1%). The burden was strongly associated with disease severity and a lower quality of life. Obese asthmatics had a significantly increased risk of a light [relative risk ratio (RRR) = 2.17; 95% CI: 1.18–4.00] or a heavy burden (RRR = 2.77; 95% CI: 1.52–5.05) compared with normal/underweight subjects. The asthmatics with frequent respiratory symptoms showed a threefold (RRR = 2.74; 95% CI: 1.63–4.61) and sixfold (RRR = 5.76; 95% CI: 3.25–10.20) increased risk of a light or a heavy burden compared with asymptomatic asthmatics, respectively. Moreover, the lower the forced expiratory volume in 1 s % predicted, the higher the risk of a heavy burden. The coexistence with chronic cough/phlegm only increased the risk of a heavy burden (RRR = 1.88; 95% CI: 1.16–3.06). An interaction was found between gender and IgE sensitization, with nonatopic asthmatic females showing the highest risk of a heavy burden (21.6%; 95% CI: 16.9–27.1%).
Conclusions:  The asthma burden is substantial in Europe. A heavy burden is more common in asthmatics with obesity, frequent respiratory symptoms, low lung function, chronic cough/phlegm and in nonatopic females.     

Tele-Interpersonal Psychotherapy Acutely Reduces Depressive Symptoms in Depressed HIV-Infected Rural Persons: A Randomized Clinical Trial

Human immunodeficiency virus (HIV)-positive rural individuals carry a 1.3-times greater risk of a depressive diagnosis than their urban counterparts. This randomized clinical trial tested whether telephone-administered interpersonal psychotherapy (tele-IPT) acutely relieved depressive symptoms in 132 HIV-infected rural persons from 28 states diagnosed with Diagnostic and Statistical Manual of Mental Disorders-IV major depressive disorder (MDD), partially remitted MDD, or dysthymic disorder. Patients were randomized to either 9 sessions of one-on-one tele-IPT (n = 70) or standard care (SC; n = 62). A series of intent-to-treat (ITT), therapy completer, and sensitivity analyses assessed changes in depressive symptoms, interpersonal problems, and social support from pre- to postintervention. Across all analyses, tele-IPT patients reported significantly lower depressive symptoms and interpersonal problems than SC controls; 22% of tele-IPT patients were categorized as a priori “responders” who reported 50% or higher reductions in depressive symptoms compared to only 4% of SC controls in ITT analyses. Brief tele-IPT acutely decreased depressive symptoms and interpersonal problems in depressed rural people living with HIV.     

CCR5 Delta32 polymorphism: associated with gallbladder cancer susceptibility

Inflammation of gallbladder is an established risk factor for gallbladder cancer (GBC) pathogenesis. Chemokine receptors play crucial role in antitumour immunity and are involved in inflammation and pathogenesis of cancers. Present study was aimed to examine the role of CCR5 Δ32 polymorphism in conferring genetic susceptibility to GBC. Present case–control study included 144 proven GBC patients and 210 healthy controls. Genotyping was done by polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method. Statistically significant difference was observed in distribution of CCR5+/Δ32 genotype ( P  = 0.028) [odds ratio (OR) = 2.850; 95% confidence interval (CI) = 1.1–7.2] and CCR5 Δ32 allele ( P  = 0.012) (OR = 3.145, 95% CI = 1.2–7.7) in GBC patients which was conferring high risk. Stratification of GBC patients showed significant association of CCR5+/Δ32 genotype and CCR5 Δ32 allele with GBC patients with and without gallstones. Analysis based on age of onset and gender suggested significant association of CCR5 Δ32 allele with early onset (<50 years) of the disease but only marginal influence of gender in CCR5 Δ32 -mediated risk of cancer. Risk was further modulated by tobacco usage and significantly increased risk was observed in tobacco users with CCR5+/Δ32 genotype. In conclusion, CCR5+/Δ32 genotype and CCR5 Δ32 allele confer significant risk for GBC particularly in patients with early onset and tobacco usage. Role of CCR5+/Δ32 polymorphism in GBC susceptibility is independent of gallstone formation.     

Dietary exclusions for improving established atopic eczema in adults and children: systematic review

Atopic eczema is the most common inflammatory skin disease of childhood in developed countries. We performed a systematic review of randomized controlled trials to assess the effects of dietary exclusions for the treatment of established atopic eczema. Nine trials (421 participants) were included, most of which were poorly reported. Six were studies of egg and milk exclusion ( n  = 288), one was a study of few foods ( n  = 85) and two were studies of an elemental diet ( n  = 48). There appears to be no benefit of an egg- and milk-free diet in unselected participants with atopic eczema. There is also no evidence of benefit in the use of an elemental or few-foods diet in unselected cases of atopic eczema. There may be some benefit in using an egg-free diet in infants with suspected egg allergy who have positive specific IgE to eggs – one study found 51% of the children had a significant improvement in body surface area with the exclusion diet as compared with normal diet (95% CI 1.07–2.11) and change in surface area and severity score was significantly improved in the exclusion diet as compared with the normal diet at the end of 6 weeks (MD 5.50, 95% CI 0.19–10.81) and end of treatment (MD 6.10, 95% CI 0.06–12.14). Despite their frequent use, we find little good quality evidence to support the use of exclusion diets in atopic eczema.     

Confirmation of the novel association at the BTNL2 locus with ulcerative colitis

Linkage in families and association in population case–control investigations have clearly shown that genes within the major histocompatibility complex region on chromosome 6p are relevant to the susceptibility and pathogenesis of ulcerative colitis (UC) and Crohn's disease. However, identifying the causative variants by fine mapping has not been conclusive. In this study using 58 single nucleotide polymorphisms (SNPs) with 616 UC cases, there was significant association with SNP rs2294881 of the (butyrophilin-like 2) BTNL2 gene with odds ratio (OR) = 2.80, confidence interval (CI) = 1.62–4.84 and P  = 5.69 × 10⁻⁴ ( P _Bonferroni = 3.3 × 10⁻²) and replication of SNP rs9268480. The missense SNP rs2076523 (K196E) showed novel association with a subset of UC cases with colectomy ( n  = 126), OR = 0.25, CI = 0.11–0.58 and P  = 4.42 × 10⁻⁴ ( P _Bonferroni = 2.56 × 10⁻²). These three associated variants within the BTNL2 gene were neither in linkage disequilibrium with each other nor correlated with the SNPs tagging the human leukocyte antigen (HLA)-DRB1*1502 and HLA-DRB1*0301 alleles.     

Effects of pets on asthma development up to 8 years of age: the PIAMA study

Background:  Recall bias may provide discrepant relationships of pet exposure with sensitization and asthma development. We studied prospectively effects of pets at home on development of sensitization, asthma and respiratory symptoms from birth up to age 8 years.
Methods:  Event history analysis was performed on annually registered data of 2951 children, participating in the PIAMA birth cohort study.
Results:  Children with a cat or dog at home at 3 months of age had a significantly lower prevalence of sensitization to inhalant allergens at age 8, but not of asthma. A cat decreased the risk of house dust mite sensitization at age 8 [odds ratio (OR) = 0.68, 95% confidence interval (CI) 0.49–0.95], a dog of pollen sensitization (OR = 0.49, 95% CI: 0.29–0.83). A cat or dog at home did not significantly affect asthma incidence in each subsequent year. From 2 years of age onwards, the incidence of wheeze (OR = 1.52, 95% CI: 1.12–2.05) and a dry cough at night (OR = 1.28, 95% CI: 1.05–1.57) was higher in children with a dog, whereas removal of a dog increased the risk of developing asthma symptoms. Comparing analyses using prospectively and retrospectively collected data on diagnosed asthma showed important recall bias.
Conclusions:  Our prospective study shows a protective effect of early presence of pets at home on sensitization to inhalant allergens, but no prevention of asthma development. Furthermore, children with pets had more frequent transient or intermittent asthma symptoms. Parental report of asthma by recall may provide spurious results of these associations.     

Polymorphisms in the promoter region of iNOS predispose to rheumatoid arthritis in south Indian Tamils

Nitric oxide synthase (NOS) catalyses the production of nitric oxide (NO) from L‐Arginine, which participates in diverse biological processes including inflammation and apoptosis. Macrophages, chondrocytes, osteoblasts and osteoclasts express inducible NOS (iNOS) at the site of synovial inflammation. NO produced at the inflamed joint may contribute to peri‐articular bone loss, mediate apoptosis and regulate Th1/Th2 balance in rheumatoid arthritis (RA). Variations in the promoter region of NOS gene regulate the nitric oxide synthase expression and iNOS (NOS2) polymorphisms have been associated with susceptibility to autoimmune disorders. Hence, this study was conducted to identify the possible contributions of NOS2 ‐1659G/A, ‐1026C/A, ‐277A/G promoter polymorphisms towards development of RA in South Indian Tamils. A total of 242 (219 females, 23 males) patients with RA (mean age 41.2 ± 10.9 years, disease duration 8.5 ± 4.3 years) and 279 age‐ and sex‐matched healthy individuals of South Indian Tamil ethnicity were genotyped for NOS2 ‐1659C/T, ‐1026G/T and ‐277A/G promoter polymorphisms by TaqMan chemistry. Nature of disease (erosive or nonerosive), the presence of extra‐articular manifestations, seropositivity for rheumatoid factor and anticyclic citrullinated peptide, serum C‐reactive protein (CRP) level and response to therapy were assessed for all patients. The three single nucleotide polymorphisms (SNPs) were in Hardy–Weinberg equilibrium. The frequency of GG genotype and G allele of NOS2‐277 was higher in patients (pc = 5.7 × 10^?9, OR = 6.09, 95% CI = 3.09–12.8 and pc = 4 × 10^?13, OR = 2.37, 95% CI = 2.06–3.62, respectively) compared to controls. Similarly, the frequency of NOS2‐1026 (rs2779249) GT genotype and the T allele was higher in patients with RA (pc = .01, OR = 1.61, 95% CI = 1.09–2.36, and pc = .04, OR = 1.40, 95% CI = 1.02–1.91, respectively). However, no significant difference in frequency of NOS2‐1659C/T polymorphism was observed between patients and controls. None of the studied SNPs were associated with erosive disease, seropositivity or extra‐articular manifestations. The ‐277A/G and ‐1026 G/T promoter polymorphisms in iNOS may confer susceptibility to RA in South Indian Tamils.