Published ahead of print on November 21, 2002, doi:10.1164/rccm.200208-851OC
© 2003 American Thoracic Society
Rhinitis Is Associated with Increased Systolic Blood Pressure in MenA Population-based StudyUnit 408, Respiratory Diseases Epidemiology, National Institute of Health and Medical Research (INSERM), Paris, and Unit 258, Cardiovascular Epidemiology, INSERM, Villejuif; and Pneumo-Allergology Service, Respiratory Diseases Department, Sainte-Marguerite Teaching Hospital, Marseille, France Correspondence and requests for reprints should be addressed to Mahmoud Zureik, M.D., Ph.D., INSERM U408, Epidémiologie des Maladies Respiratoires, Faculté Xavier Bichat, 16 rue Henri Huchard, 75018 Paris, France. E-mail: zureik{at}vjf.inserm.fr
An association between impaired lower respiratory function and cardiovascular risk factors, such as hypertension, is often reported but it is unknown whether there is a relationship between upper airway disorders and cardiovascular risk factors, despite evidence that upper and lower respiratory tract disorders are closely linked. Our objective was to assess whether rhinitis is associated with arterial blood pressure and hypertension. In a population-based study of 330 adults aged 2856 years, as part of the European Community Respiratory Health Survey, rhinitis was assessed by means of a questionnaire, and cardiovascular data were obtained using a questionnaire and by measuring blood pressure. Systolic blood pressure (SBP) was higher in men with rhinitis than in men without rhinitis (130.6 ± 12.7 mm Hg versus 123.5 ± 13.9 mm Hg; p = 0.002), and it was still the case after adjustment for cardiovascular and respiratory confounding factors. Hypertension was more frequent in men with rhinitis than in men without rhinitis, even after multivariate adjustment (odds ratio = 2.6, 95% confidence interval = [1.145.91]). The observation of SBP levels according to whether men have no rhinitis, seasonal rhinitis, or perennial rhinitis was compatible with a doseresponse relationship (p for trend = 0.02). In conclusion, rhinitis is strongly associated with SBP and hypertension in men. Blood pressure should be regularly checked in men with rhinitis.
Key Words: rhinitis blood pressure hypertension Numerous epidemiologic studies have suggested that impaired lower respiratory function (expressed by the FEV1 and/or the peak expiratory flow) is associated with some cardiovascular risk factors (1) and with atherosclerosis (2), arterial stiffness (3), cardiovascular diseases, and mortality (4, 5). However, the physiopathologic mechanisms underlying these associations are not known. In contrast, no studies have assessed the association between upper airway disorders, such as rhinitis, and cardiovascular alterations, although many epidemiologic studies have shown that lower and upper airway disorders are associated (68). In addition, rhinitis might be related to cardiovascular risk factors, particularly hypertension (9), as rhinitis is associated with snoring and obstructive sleep apnea (OSA) (812) and as snoring and OSA are associated with hypertension (1316). The high prevalence of both rhinitis and hypertensionapproximately 25% of the population living in industrialized countries (17, 18)intensifies the interest to know whether there is actually an association between rhinitis and arterial blood pressure. The present study was performed with this purpose.
Study Participants Data were collected in Hôpital Bichat (Paris, France), between October 1999 and May 2001, as part of the follow-up phase of the European Community Respiratory Health Survey (ECRHS-II). The methods used in this study have been described elsewhere (19). Briefly, 660 subjects aged 2044 years were randomly selected from the electoral rolls of the 18th district of Paris. These subjects were examined at the hospital between 1992 and 1993 (ECRHS-I). Three hundred and thirty subjects could be contacted again and accepted to be examined a second time between 1999 and 2001 for ECRHS-II.
Study Protocol FVC and FEV1 were measured with a water-sealed bell spirometer (Biomedin, Padova, Italy). Lung function was assessed by FEV1 %pred and FEV1 %FVC. Predicted FEV1 values were calculated according to sex, height, and age (25). In addition to the general ECRHS-II protocol, the participants were asked to complete a standardized questionnaire on conventional cardiovascular risk factors, and their arterial pressure was measured. Both systolic and diastolic blood pressures (SBP and DBP) were measured with a digital electronic tensiometer (Model CP750, Omron Electronics SARL, Fontenay sous Bois, France). Two independent measurements were taken with a 5-minute interval, with the subjects in a lying position. We used the second values for the statistical analyses. Subjects were classified as being hypertensive when their SBP was at least 140 mm Hg, and/or their DBP was at least 90 mm Hg, and/or they reported using an antihypertensive treatment (26). Patients were considered to have hypercholesterolemia if they answered "yes" to at least one of the following questions: "Have you ever been told your cholesterol level was too high?" and "Do you currently use any lipid-lowering drugs?" Body mass index (BMI) was calculated as weight in kilograms divided by the square of height in meters. Nonfasting total serum cholesterol levels were determined using standard methods. The protocol was approved by the French Ethics Committee for Human Research and by the National Committee for Data Processing and Freedom. Written informed consent was obtained from each subject before inclusion in the study.
Statistical Analysis Data were analyzed with version 8.1 of SAS (SAS Institute, Cary, NC). All analyses were performed in men and in women separately. In univariate analyses, with rhinitis or hypertension as the dependent variable, chi-square tests and t tests were used to compare qualitative and quantitative variables, respectively. The relationships between SBP or DBP and quantitative variables were assessed with Pearson's correlation coefficient (r). In multivariate analyses, where all potential confounding factors were taken into account, the mean arterial blood pressures (± SD) of subjects with and without rhinitis were compared using analysis of covariance. Univariate and multivariate logistic regressions were used to analyze the relationship between rhinitis and hypertension. p Values below 0.05 were considered to be significant.
Study Population Table 1 shows the characteristics of the study population according to sex. BMI was higher among men than among women. Asthma and rhinitis tended to be less frequent in men than in women. SBP and DBP were higher in men, and hypertension was more frequent.
Associations between Blood Pressure and Demographic, Respiratory, and Cardiovascular Risk Factors, by Sex Age was significantly associated with SBP in women (r = 0.27, p < 0.001) and tended to be so in men (r = 0.14; p = 0.08). SBP was positively associated with BMI in both men and women (r = 0.32, p < 0.001 and r = 0.33, p < 0.001, respectively) and with total serum cholesterol level (r = 0.20, p = 0.02 and r = 0.24, p = 0.002, respectively). SBP was not associated with cumulative smoking exposure (in pack-years) among men (p = 0.8) but tended to be negatively so among women (p = 0.07). SBP was higher in men with asthma than in men without asthma (133.4 ± 11.9 mm Hg versus 125.3 ± 13.9 mm Hg; p = 0.03). SBP was not associated with either FEV1 %pred or FEV1 %FVC in men (r = -0.009, p = 0.90 and r = -0.10, p = 0.20). In women, SBP tended to be negatively associated with FEV1 %pred (r = -0.13, p = 0.08) but was not associated with FEV1 %FVC (r = 0.05, p = 0.50). Similar patterns of results were observed for DBP and for hypertension.
Associations between Rhinitis and Demographic, Respiratory, and Cardiovascular Risk Factors, by Sex
Associations between Rhinitis and Arterial Blood Pressure, by Sex Men with rhinitis had a higher SBP than did men without rhinitis (130.6 ± 12.7 versus 123.5 ± 13.9 mm Hg, p = 0.002) (Table 3) . This result remained similar when common potential confounding factors (age, BMI, hypercholesterolemia, and smoking status) were taken into account (129.9 ± 13.2 versus 123.6 ± 13.3 mm Hg, p = 0.006). Additional adjustment for asthma and/or FEV1 (FEV1 %pred or FEV1 %FVC) did not alter this result. In the models including asthma and rhinitis simultaneously, the association between SBP and asthma observed in the univariate analysis disappeared. No association was found between rhinitis and SBP in women either before or after adjustment for common potential confounding factors (Table 3). Rhinitis was not associated with DBP in men or in women (Table 3).
When the analysis was performed in men without asthma alone, SBP was still higher among subjects with rhinitis than among ones without rhinitis (129.2 ± 13.0 versus 123.5 ± 14.0 mm Hg, p = 0.03). This result remained similar after adjustment for the potential confounding factors (128.2 ± 13.1 versus 123.6 ± 13.0 mm Hg, p = 0.07). Furthermore, when men were stratified according to their smoking status, SBP was always higher in men with rhinitis than in men without rhinitis in each stratum, before and after multivariate adjustment, although statistical significance was not always reached (Table 4) .
Treatment was also taken into account. Eighteen of the men had used corticoids in the last 12 months (10 subjects used steroid nasal sprays alone, 5 used inhaled steroids alone, 2 used nasal sprays plus inhaled steroids, and 1 used nasal sprays plus oral steroids). In the 127 men who had not been treated with steroids, a higher SBP was still observed among men with rhinitis than among men without rhinitis (129.8 ± 12.8 versus 123.9 ± 14.0 mm Hg, p = 0.02). This result remained similar after adjustment for the potential confounding factors (128.8 ± 12.6 versus 124.1 ± 12.6 mm Hg, p = 0.05). Lastly, we studied SBP according to whether the men had seasonal or perennial rhinitis (Figure 1) . SBP was higher as symptoms of rhinitis were more frequent (p for trend = 0.02 in univariate analysis and 0.03 after adjustment for confounding factors).
Hypertension Hypertension was more frequent in men with rhinitis than in men without rhinitis (35.7 versus 15.6%, p = 0.005; odds ratio = 3.0, 95% confidence interval = [1.376.64]), and this was still the case after adjustment for the potential confounding factors (odds ratio = 2.6, 95% confidence interval = 1.145.91). A similar trend was observed among men without asthma, after stratification according to smoking status, and in men who had not received steroids. There was also a positive association between the frequency of hypertension and the frequency of symptoms of rhinitis: hypertension was present in 15.6% of the men without rhinitis, 30.8% of the men with rhinitis with seasonal symptoms, and 34.4% of the men with rhinitis with perennial symptoms (p for trend = 0.02).
Main Findings We found that SBP was higher in men with rhinitis than in men without rhinitis, even after adjustment for major known confounding factors. Furthermore, SBP was higher in men with rhinitis than in men without rhinitis in the subgroup of men without asthma and in men who had not received steroids, and tended to be higher in each stratum of cumulative smoking exposure. Hypertension was more frequent in men with rhinitis than in men without rhinitis.
Data Validity Finally, the factors we found to be associated with rhinitis are usually reported to be so in the literature (6, 7, 29). We also found that arterial blood pressure (SBP, DBP, and hypertension) was associated with the expected cardiovascular risk factors such as sex, age, BMI, and cholesterol (30). We did not find any relationship between cumulative smoking exposure and blood pressure. This result is consistent with previously published studies that showed that smoking is not a cause of persistent hypertension. This relationship is indeed much debated: some authors reported a positive association between smoking and hypertension whereas others reported a lower arterial blood pressure in current smokers than in nonsmokers or found a higher rate of hypertension in former smokersrather than current smokerscompared with nonsmokers (31, 32).
Strength of the Relationship between Rhinitis and SBP and Hypertension We also found that rhinitis was associated with hypertension, even after multivariate adjustment. This finding emphasizes the potential clinical relevance of our study as hypertension identifies a category of patients with a high cardiovascular risk profile. We checked the association between rhinitis and blood pressure among men without asthma, as asthma was associated with both rhinitisin our study and in the literature (6, 7)and blood pressure. Associations between asthma and cardiovascular diseases (35), SBP (36), and hypertension (36, 37) have previously been suggested in some studies. The fact that in our study the association between asthma and SBP disappeared only when rhinitis was taken into account suggests that this association could be partly explained by rhinitis. We also analyzed men who had not received steroids because corticosteroids may increase blood pressure (38). In the different subgroups (i.e., subjects without asthma and men who had not been treated with steroids), SBP was still higher in men with rhinitis than in men without rhinitis. In each smoking stratum, SBP was also higher in men with rhinitis than in men without rhinitis, but statistical significance was not always reached, probably because of the small number of subjects. The results of our additional analysis of SBP level according to whether rhinitis was seasonal or perennial are consistent with the possibility of a doseresponse relationship.
Possible Mechanisms Rhinitis has previously been shown to be associated with both the main symptoms of OSA (snoring and daytime sleepiness) and OSA itself (10, 12). This is probably due to partial or complete nasal obstruction being inherent in rhinitis (11). In turn, OSA and surrogate markers, like snoring, are associated with arterial blood pressure and/or hypertension (13, 15, 16), and there is strong evidence that the mechanisms of blood pressure regulation are severely affected by OSA and consequent hypoxia (14). Rhinitis was found to be associated with SBP but not with DBP. It is well known that measurement errors and intra-individual variability are greater for DBP than for SBP. In addition, SBP and DBP do not depend on the same hemodynamic mechanisms. In contrast to DBP, which is primarily due to the vascular resistance of small peripheral arteries, SBP may increase due to three main factors: an increase in the velocity of ventricular ejection and/or stroke volume, a reduction in the viscoelastic properties of the large arteries, and a modification in the timing of the reflected waves within the arterial tree (39). Thus, elevated SBP is not systematically combined with elevated DBP (40). In addition, it has been shown that SBP is a stronger predictor of adverse cardiovascular events and total mortality than is DBP (41). Nevertheless, the mechanisms that might explain the differential association of SBP and DBP with rhinitis are unknown. Further studies are thus needed to investigate the nature of the association between rhinitis and arterial blood pressure.
Why in Men and Not in Women? In addition, if OSA is actually implicated in the association between rhinitis and hypertension, this is consistent with the absence of this association in the women in our sample. Indeed, before menopause, women are protected from OSA. A recent study, performed on a large random sample of the general population, reported that the prevalence of OSA is quite low in premenopausal women compared with that in men and postmenopausal women (45).
Conclusion
The authors thank the Center of Clinical Investigations (CIC) staff of the Bichat Teaching Hospital for its valuable contributions to the data collection, and especially Isabelle Poirier for her reliable and continuous technical assistance.
Supported by UCB Pharma-France (for the data collection of the European Community Respiratory Health Survey follow-up phase [CRHS-II] in Paris). Received in original form August 12, 2002; accepted in final form November 18, 2002
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