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PubMed1998

Natural bright light exposure in the summer and winter in subjects with and without complaints of seasonal mood variations.

BACKGROUND: Considering the success of bright light therapy in seasonal affective disorders, it was suggested that seasonal mood disorders are triggered by decreased exposure to bright light in the winter; however, no previous studies have used objective measures to assess seasonal patterns of bright light illumination in subjects with seasonal mood variations. METHODS: Eleven subjects reporting seasonal mood variations and 8 control subjects had their levels of natural bright light (BL) exposure measured for 5-6 days with an ambulatory monitor during both the summer and winter, at a latitude of 45 degrees 31'N. RESULTS: Both groups received significantly more BL in the summer than in the winter, but there was no difference between the two groups for the pattern of BL exposure, including total duration, daily distribution, and amplitude of seasonal variation. CONCLUSIONS: These results suggest that complaints of seasonal mood variations are not caused by a differential pattern in bright light exposure compared to normals. It is possible, however, that some individuals are more sensitive than others to variations in natural bright light. Whether an increased vulnerability is due to a more fragile affective state or to a lower sensitivity to light remains to be determined.

Adult↗
PubMedDate not supplied

Summer and winter patterns of seasonality in Chinese college students: a replication.

The goal of this study is to replicate an earlier epidemiological finding of seasonal changes in mood and behavior among Chinese medical students using an independent study population. Three hundred nineteen college students were surveyed with a Chinese version of the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Beck Depression Inventory (BDI) in Jining, China, during March of 1996. The frequency of seasonal patterns and prevalence rates of seasonal affective disorder (SAD) were estimated and compared with data from the medical student survey conducted in the same city. The mean Global Seasonality Score (GSS) of this college student sample was 9.9 +/- 4.9; 84% of the subjects reported some problems with the changing seasons. Summer difficulties were more prevalent than winter difficulties by a ratio of 1.9 to 1 (38.9% v 20.1%). The estimated rates of summer SAD and subsyndromal-SAD (s-SAD) were 7.5% and 11.9%, respectively, as compared with the corresponding winter figures of 5.6% and 6.3%. In addition, the prevalence estimates of winter pattern or winter SADs were higher in males than in females, but the corresponding summer figures showed no gender difference. Compared with the data from the medical student survey, this college student sample had a higher GSS (P < .01) but comparable summer to winter and female to male ratios for the prevalence of SADs (P > .05). These results replicate our previous findings that seasonal problems are common in China, but the predominant problems are summer difficulties rather than winter difficulties, and there is no female preponderance in the prevalence estimates of such problems. Both findings stand in contrast to most Western studies but are consistent with the only other published study performed in the Orient.

Adult↗
PubMed1990

Different prevalence and degree of nonspecific bronchial hyperreactivity between seasonal and perennial rhinitis.

From the patients observed at our respiratory allergology service, we selected patients with rhinitis only, without any past or present respiratory symptoms, for our study. All these patients had normal pulmonary function, were administered carbachol or methacholine bronchial challenges, and had one or more skin reactions to perennial or seasonal allergens. Patients were allocated to three groups: group A, patients with seasonal rhinitis who were administered nonspecific challenges out of season; group B, patients with seasonal rhinitis tested during the season; and group C, patients with perennial rhinitis. The three groups were divided into subgroups according to the duration in years of rhinitis and to the degree of nonspecific bronchial responsiveness. The distribution into four groups of reactivity, arbitrarily defined as normal and mildly, moderately, and severely increased reactivity, was as follows: group A, 124, 21, 30, 22; group B, 75, 15, 7, and 21: and group C, 69, 17, 39, and 72, respectively. The patients of group C (perennial rhinitis) demonstrated a distribution significantly (p less than 0.001) different from subjects with seasonal rhinitis, both group A and group B. Our results are consistent with the hypothesis that perennial rhinitis is much more important than seasonal rhinitis as a risk factor for developing nonspecific bronchial hyperresponsiveness.

Age Factors↗
PubMed1998

Lack of seasonal variation of symptoms in patients with chronic fatigue syndrome.

Several of the symptoms involved in chronic fatigue syndrome (CFS) such as fatigue, hypersomnia, hyperphagia, weight gain, and mood show seasonal variations in the general population. The aim of this study was to investigate whether patients with CFS experience seasonal fluctuations in these symptoms as well. Seasonal variation of symptoms was assessed in a group of 41 patients with CFS and 41 controls closely matched for age, gender, and city of residence. Participants were recruited across the US and were asked to complete the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Profile of Mood States (POMS). CFS patients showed significantly lower scores on multiple SPAQ-derived measures as compared with controls. These included seasonal variation in energy, mood, appetite, weight, and sleep length. Patients also reported a significantly reduced sensitivity toward sunny, dry, and long days than controls. No association was noted between intensity of seasonal changes and severity of depressive symptoms. Patients with CFS exhibit an abnormally reduced seasonal variation in mood and behavior and would not be expected to benefit from light therapy.

Adult↗
PubMed1999

Exhaled and nasal NO levels in allergic rhinitis: relation to sensitization, pollen season and bronchial hyperresponsiveness.

Exhaled nitric oxide is a potential marker of lower airway inflammation. Allergic rhinitis is associated with asthma and bronchial hyperresponsiveness. To determine whether or not nasal and exhaled NO concentrations are increased in allergic rhinitis and to assess the relation between hyperresponsiveness and exhaled NO, 46 rhinitic and 12 control subjects, all nonasthmatic nonsmokers without upper respiratory tract infection, were randomly selected from a large-scale epidemiological survey in Central Norway. All were investigated with flow-volume spirometry, methacholine provocation test, allergy testing and measurement of nasal and exhaled NO concentration in the nonpollen season. Eighteen rhinitic subjects completed an identical follow-up investigation during the following pollen season. Exhaled NO was significantly elevated in allergic rhinitis in the nonpollen season, especially in perennially sensitized subjects, as compared with controls (p=0.01), and increased further in the pollen season (p=0.04), mainly due to a two-fold increase in those with seasonal sensitization. Nasal NO was not significantly different from controls in the nonpollen season and did not increase significantly in the pollen season. Exhaled NO was increased in hyperresponsive subjects, and decreased significantly after methacholine-induced bronchoconstriction, suggesting that NO production occurs in the peripheral airways. In allergic rhinitis, an increase in exhaled nitric oxide on allergen exposure, particularly in hyperresponsive subjects, may be suggestive of airway inflammation and an increased risk for developing asthma.

Adolescent↗
PubMed2001

A longitudinal investigation of seasonal variation in mood.

A prospective panel study was conducted to measure seasonality of mood in a random community sample in Melbourne, Australia (N = 245). Based on research into the structure of human mood, it was predicted that a lowering of mood in winter relative to summer would be observed in positive affect (PA) and behavioral engagement (BE), but not negative affect (NA). These variables were measured across summer and winter for 3 years. Consistent with the majority of research in the Northern Hemisphere, analyses on the entire sample found evidence of a small prospective season effect on the BE scale (explaining 2.1% of variance in BE scores). Also, as expected, no season effect was seen on the NA scale. In the entire sample, the season effect was not significant for PA, but joint factor analysis of the BE, PA, and NA scales confirmed that the season effect seen in the BE scale was largely due to items that were pure measures of PA. Winter pattern seasonality was both reliable across measures and significantly more marked among the subgroup of respondents who self-identified winter pattern of mood on the Seasonal Pattern Assessment Questionnaire.

Affect↗
PubMed1986

Seasonal differences in breast-feeding in rural Egypt.

Two surveys in Upper and Lower rural Egypt allowed an analysis of the seasonality of infant feeding. The first, including 937 children, was conducted during the relatively cool season of low diarrhea incidence in January-April 1978; the second, including 976 children, took place during the hot season of high diarrhea incidence in August-September 1980. Of infants 6-11 mo old, the proportion exclusively breast-feeding was greater in the hot-season survey (40% vs 16% in Lower Egypt, p less than 0.01; 36% vs 22% in Upper Egypt, p less than 0.01). Of children 12-17 mo old, a higher proportion were completely weaned during the hot season in Lower Egypt only (28% vs 14%, p less than 0.01). This difference was explained by an increase in pregnancy rates during the hot season resulting in less breast-feeding. Seasonal variation must be considered in the interpretation of infant-feeding surveys.

Breast Feeding↗
PubMed1988

An analysis of the seasonal variation of coronary heart disease and respiratory disease mortality in New Zealand.

The seasonal variation of coronary heart disease mortality rates in New Zealand is analysed by age, sex and race using monthly national mortality data for the period 1970-83. A 35% variation from the winter peak to summer low is found in the crude mortality rate, but the size of the seasonal variation is age-dependent, being more pronounced in the elderly, and more so in males than in females. The hypothesis that respiratory infections are linked to coronary heart disease, and that their seasonal occurrence explains the seasonal variation in coronary rates, is examined by an analysis of the association between coronary disease and respiratory disease mortality rates. By partial correlation analysis and by examining the residual correlation after filtering the seasonal variation from both series, it is suggested that the season acts as a confounding factor to cause an apparent association between the two rates. After controlling for season there is a tenuous relationship, but it is apparent only in the elderly.

Adult↗
PubMed1999

Mood, latitude, and seasonality among adolescents.

OBJECTIVE: To examine the effect of sex, latitude, and behavior problems on symptoms related to pediatric seasonal affective disorder among seventh and ninth graders. METHOD: A school survey including a modified version of the Seasonal Pattern Assessment Questionnaire was carried out in 2 Finnish cities located in the 60th and 67th northern latitudes. Altogether 1,458 questionnaires were analyzed, representing 89% of the target population. RESULTS: Seasonal changes in mood and behavior were commonly reported among seventh and ninth graders. A high Global Seasonality score (> 95th percentile) was associated with female gender and emotional and hyperactivity symptoms. During February and March, girls living in the 67th latitude reported more seasonal distress than girls living at the 60th latitude. CONCLUSIONS: It is important to recognize pediatric seasonal affective disorder and related problems among adolescents. Seasonal alterations in child and adolescent behavior are not well understood and need to be investigated more thoroughly.

Adolescent↗
PubMed1996

Subsyndromal seasonal affective disorder in Antarctica.

The seasonality of depressed mood was examined in 70 men and women who spent the 1991 austral winter at three American research stations in Antarctica. Seasonal Pattern Assessment Questionnaire global seasonality scores increased significantly from late summer (February/March) to midwinter (July/August; p < .001). Only one case of seasonal affective disorder (SAD) was found during midwinter, but the prevalence of subsyndromal SAD increased significantly, from 10.5 to 28.4 per 100, during this period. Station latitude was significantly associated with SAD-specific symptoms and global Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorders Version scores in midwinter and in early spring (October). The results suggest that even clinically normal individuals are likely to experience symptoms of subsyndromal SAD in high latitude environments, that these variations become more pronounced with increasing latitude, and that they can be detected through repeated administrations of instruments such as the Seasonal Pattern Assessment Questionnaire and Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorders Version.

Adult↗
PubMed2004

Defective suppression of Th2 cytokines by CD4CD25 regulatory T cells in birch allergics during birch pollen season.

BACKGROUND: CD4(+)CD25+ regulatory T cells suppress proliferation and cytokine production by human T cells both to self-antigens and exogenous antigens. Absence of these cells in human newborns leads to multiple autoimmune and inflammatory disorders together with elevated IgE levels. However, their role in human allergic disease is still unclear. OBJECTIVE: This study aimed to evaluate the capacity of CD4(+)CD25+ regulatory T cells to suppress proliferation and cytokine production outside and during birch-pollen season in birch-allergic patients relative to non-allergic controls. METHODS: CD4+ cells were obtained from blood of 13 birch-allergic patients and six non-allergic controls outside pollen season and from 10 birch-allergic patients and 10 non-allergic controls during birch-pollen season. CD25+ and CD25- fractions were purified with magnetic beads and cell fractions, alone or together in various ratios, were cultured with antigen-presenting cells and birch-pollen extract or anti-CD3 antibody. Proliferation and levels of IFN-gamma, IL-13, IL-5 and IL-10 were measured by thymidin incorporation and ELISA, respectively. Numbers of CD25+ cells were analysed by flow cytometry. RESULTS: CD4(+)CD25+ regulatory T cells from both allergics and non-allergics potently suppressed T cell proliferation to birch allergen both outside and during birch-pollen season. However, during season CD4(+)CD25+ regulatory T cells from allergic patients but not from non-allergic controls were defective in down-regulating birch pollen induced IL-13 and IL-5 production, while their capacity to suppress IFN-gamma production was retained. In contrast, outside pollen season the regulatory cells of both allergics and non-allergic controls were able to inhibit T-helper 2 cytokine production. CONCLUSION: This is the first study to show differential suppression of Th1 and Th2 cytokines, with CD4(+)CD25+ regulatory T cells from birch-pollen-allergic patients being unable to down-regulate Th2, but not Th1 responses during birch-pollen season.

Adult↗
PubMed2003

Dissimilarity between seasonal changes in airway responsiveness to adenosine-5'-monophosphate and methacholine in patients with grass pollen allergic rhinitis: relation to induced sputum.

BACKGROUND: In patients with allergic rhinitis, bronchial hyperresponsiveness (BHR) and airway inflammation may increase during pollen exposure. BHR can be assessed by adenosine-5'-monophosphate (AMP) or methacholine challenge. It has been suggested that BHR to AMP is more closely related to airway inflammation than BHR to methacholine. Seasonal allergic rhinitis offers a dynamic model to study changes in BHR and airway inflammation during natural allergen exposure. METHODS: We measured BHR [provocative concentration causing a 20% fall (PC(20)) in forced expiratory volume in 1 s (FEV(1))] to AMP and methacholine, and induced sputum cells in 16 rhinitis patients before and during the 2001 grass pollen season. RESULTS: There was a decrease in PC(20) methacholine during pollen exposure (geometric mean PC(20) from 3.22 to 1.73 mg/ml, p = 0.0023), whereas no reduction was observed for PC(20) AMP (p = 0.11). There was no increase in sputum eosinophils [pre: 0.69% (95% confidence interval 0.22-2.07); during: 1.85 (0.55- 5.6), p = 0.31]. Although the correlation of log PC(20) methacholine and log PC(20) AMP at baseline was good (r = 0.76, p = 0.001), individual seasonal changes (doubling concentrations) in PC(20) methacholine were not correlated with changes in PC(20) AMP (rho = 0.21, p = 0.44). There was no correlation between baseline log PC(20) methacholine or seasonal changes in PC(20) methacholine and sputum eosinophils (p > 0.12, all correlations). In contrast, there was a significant correlation between seasonal changes in PC(20) AMP and changes in sputum eosinophils (rho = -0.59, p = 0.025). CONCLUSIONS: These data show dissimilarity between seasonal changes in PC(20) AMP and methacholine in patients with seasonal allergic rhinitis. Moreover, PC(20) AMP seems to be more closely related to sputum eosinophils than PC(20) methacholine. The clinical significance of this discrepancy is unclear.

Adenosine Monophosphate↗
PubMed2000

Seasonal variations in mood and behavior among Chinese medical students.

OBJECTIVE: The goal of this study was to estimate the frequency of seasonal variations in mood and behavior among Chinese medical students. METHOD: A total of 1,358 medical students were surveyed with Chinese versions of the Seasonal Pattern Assessment Questionnaire and the Beck Depression Inventory in Jining, China. RESULTS: The mean global seasonality score was 8.3 (SD=3.6) out of a possible 24; 81.7% (N=1,110) of the subjects reported some trouble adapting to changing seasons. Summer difficulties were more common than winter difficulties by a ratio of 3:2; estimated rates of summer seasonal affective disorder and subsyndromal seasonal affective disorder were 4.4% and 8.0%, respectively, compared with corresponding winter rates of 2.4% and 5.7%. CONCLUSIONS: These results suggest that seasonal variations in mood and behavior are common in China. The predominance of summer difficulties stands in contrast to that in most Western studies and is consistent with the only other published study performed in Asia.

Adolescent↗
PubMed1996

Seasonal changes in affective state measured prospectively and retrospectively.

BACKGROUND: The study was designed to investigate whether seasonal mood and behavioural changes are detectable prospectively in a non-clinical population in the way they have been reported in retrospective studies. The specificity of any seasonal fluctuation in affective state was also investigated by measuring anxiety as well as depression. METHOD: To measure seasonal fluctuations in affect and behaviour prospectively, 25 women were interviewed every month for one year using four scales (depression, anxiety, stress, and behavioural change). Retrospective accounts of mood and behaviour at the end of the year were collected with the Seasonal Pattern and Assessment Questionnaire (SPAQ). RESULTS: Seasonal depression peaked in winter as did atypical behaviour when measured either prospectively or retrospectively, but the difference between winter and summer was much more pronounced in the retrospective data. No seasonal effect was found for anxiety or psychosocial stressors. CONCLUSIONS: The results obtained by retrospective techniques have limited reliability. In the future, more prospective studies with unbiased, standardised instruments are recommended to measure seasonal variations in affect and behaviour.

Adult↗
PubMed2003

Evaluation of the safety of palivizumab in the second season of exposure in young children at risk for severe respiratory syncytial virus infection.

BACKGROUND: Palivizumab reduces respiratory syncytial virus (RSV) hospitalisations in high-risk infants. Those with severe bronchopulmonary dysplasia may require two seasons of prophylaxis. There is concern that this humanised antibody might cause an adverse immune response in a second season of use. OBJECTIVE: To evaluate and compare the occurrence of anti-palivizumab antibodies and clinical adverse events in subjects receiving monthly palivizumab injections for a first and second season, and to assess frequency and severity of RSV disease in the two groups. DESIGN AND PATIENTS: Subjects aged or=1 : 80). Serum palivizumab concentrations were similar for the two groups. Nine (12.7%) first season and 8 (12.7%) second season subjects experienced one or more serious adverse events; most were respiratory and all were considered to be not or probably not related to palivizumab. No deaths occurred during the study. CONCLUSIONS: Monthly palivizumab injections were not associated with adverse immune responses or adverse events in young children receiving palivizumab for one or two seasons. Children receiving palivizumab for a second season did not experience more severe adverse events than those receiving it for the first time.

Antibodies, Monoclonal↗
PubMed2005

[Is the frequency of pre-seasonal manifestation in patients with Japanese cedar pollinosis so high?].

BACKGROUND: Based on subjective symptom, it has been documented that so high as 21 to 62% of patients with Japanese cedar pollinosis has pollinosis symptom before the start of pollen season. Since this is not objectively evidenced, we aimed to clarify whether or not it is true. METHOD: We quantified intranasal pollen by means of our nasal lavage method in patients with Japanese cedar pollinosis shortly after the onset of symptom during pre-, mid- and post-season from 1997 to 2005. RESULT: Significant differences in intranasal pollen count were revealed among mid- and pre- and post-season. Intra-nasal pollens, so few as 1 or less, were found in 67.8% of patients having pre-seasonal symptom, while in 12.5% during the mid-season. The majority of patients had not sufficient number of intra-nasal pollen to induce pollinosis. However, the intranasal pollen counts in preseason were related well with total airborne pollen amount in next spring. Pollens other than Japanese cedar pollen were also detected in lavages. CONCLUSION: Many factors such as method of pollen survey, personal nasal hyper-reactivity and irritation by cold air, or with pollens other than Japanese cedar may cause the pre-seasonal pollinosis symptom. High frequencies of pre-seasonal onset in previous reports may be over-estimated due to inaccurate diagnosis of Japanese cedar pollinosis.

Adult↗
PubMed1984

[Reactivity of the bronchi in pollen rhinitis and pollen asthma the before and during the pollen season].

Nonspecific bronchial reactivity was investigated during and out of the pollen season in 28 pollen-allergic asthmatics and 25 hay fever patients without bronchial asthma. The degree of the reactivity was measured by the decrease of inspiratory specific airway conductance (sGI) after voluntary hyperventilation. Before hyperventilation the mean values for the sGI in both groups of patients were within the low normal range and revealed no seasonal fluctuations. During the pollen season 26 (93%) asthmatics and 14 (56%) hay fever patients showed bronchial hyperreactivity. Out of season 22 (79%) asthmatics and only 8 (32%) hay fever patients were hyperreactive. Thus, in the absence of the relevant allergens, most of the pollen sensitive asthmatics showed a significant increase in unspecific bronchial reactivity which was somewhat higher during the pollen season. The seasonal increase of bronchial reactivity in hay fever patients suggests a relationship with pollen asthma. 12 pollen-allergic asthmatics, who were examined again in the next pollen season after one period of preseasonal specific hyposensitization with pollen extracts, displayed a significant decrease in nonspecific bronchial reactivity.

Adult↗
PubMed2004

Seasonal variation in serum cholesterol levels: treatment implications and possible mechanisms.

BACKGROUND: A variety of studies have noted seasonal variation in blood lipid levels. Although the mechanism for this phenomenon is not clear, such variation could result in larger numbers of people being diagnosed as having hypercholesterolemia during the winter. METHODS: We conducted a longitudinal study of seasonal variation in lipid levels in 517 healthy volunteers from a health maintenance organization serving central Massachusetts. Data collected during a 12-month period for each individual included baseline demographics and quarterly anthropometric, blood lipid, dietary, physical activity, light exposure, and behavioral information. Data were analyzed using sinusoidal regression modeling techniques. RESULTS: The average total cholesterol level was 222 mg/dL (5.75 mmol/L) in men and 213 mg/dL (5.52 mmol/L) in women. Amplitude of seasonal variation was 3.9 mg/dL (0.10 mmol/L) in men, with a peak in December, and 5.4 mg/dL (0.14 mmol/L) in women, with a peak in January. Seasonal amplitude was greater in hypercholesterolemic participants. Seasonal changes in plasma volume explained a substantial proportion of the observed variation. Overall, 22% more participants had total cholesterol levels of 240 mg/dL or greater (> or =6.22 mmol/L) in the winter than in the summer. CONCLUSIONS: This study confirms seasonal variation in blood lipid levels and suggests greater amplitude in seasonal variability in women and hypercholesterolemic individuals, with changes in plasma volume accounting for much of the variation. A relative plasma hypervolemia during the summer seems to be linked to increases in temperature and/or physical activity. These findings have implications for lipid screening guidelines. Further research is needed to better understand the effects of a relative winter hemoconcentration.

Adult↗