Trends in news coverage about skin cancer prevention, 1993-2006: increasingly mixed messages for the public

Objective: To provide a comprehensive overview of trends in news coverage about sun protection issues in an Australian setting over a 14‐year period. Methods: A content analysis was performed on all relevant articles (N=547) published in two major daily newspapers, The Age and the Herald Sun, from 1993 to 2006. Articles were coded for article type, prominence, theme, spokesperson, topic slant and opinion slant. Results: The most frequent themes were the health effects of ultraviolet (UV) radiation exposure (24% of articles), education/prevention (14%) and product issues (12%). Themes that became more dominant over time were vitamin D issues, solaria issues and fake tans. Sixty per cent of articles included a pro‐sun protection spokesperson and 12% an anti‐sun protection spokesperson, with the profile of anti‐sun protection spokespeople increasing over time. Half the articles reported on topics positive for sun protection, whereas 18% reported on negative topics; however, this difference narrowed considerably from 2001 onwards. In opinionated articles, the opinions expressed by authors were mainly positive (57%) rather than negative (7%) for sun protection. Conclusions and implications: The findings suggest that the mix of sun protection issues covered and views of sun protection have changed over time, resulting in greater coverage of controversies and issues not necessarily positive for sun protection objectives. These findings imply that evaluation of paid skin cancer prevention public education campaigns may need to take account of the changing news media environment in which they take place.     

“Prescribing sunshine”: a national,cross-sectional survey of 1,089 New Zealand general practitioners regarding their sun exposure and vitamin D perceptions,and advice provided to patients

ABSTRACT: BACKGROUND: The health effects of ultraviolet radiation vary according to wavelength, timing and pattern of exposure, personal characteristics and practices. Negative effects include skin cancers, eye diseases and immune suppression; positive effects primarily relate to endogenous vitamin D production which protects against bone disease. Drafting comprehensive guidelines regarding appropriate sun protective behaviours and vitamin D sufficiency is challenging. Advice given by general practitioners is potentially influential because they are widely respected. METHODS: A survey instrument was developed, pre-tested and provided to practising GP's, either by on-line link or mailed, reply paid hard-copy. Odds ratios, differences in means, or ratios of geometric means from regression models are reported for potential predictor variables with 95 % confidence intervals. RESULTS: Data (demographic, training, practicing, information accessing, confidence in vitamin D knowledge) suitable for analysis were obtained from 1,089 GPs (32 % participation). Many (43 %) were 'not at all confident' about their vitamin D knowledge. Recent information led 29 % to recommend less sun protection during winter months and 10 % less all year. Confidence was positively associated with non-'Western' medical training, information sources read and practising in a metropolitan centre with a medical school. Reading the Melanoma Clinical Practice Guidelines was associated with lower estimates of the amount of summer sun exposure required to obtain adequate vitamin D. Increasing years in practice was negatively associated with provision of recommended advice about summer and winter sun protection. Greater concern about vitamin D than skin cancer was expressed by females and those in practice longer. CONCLUSIONS: Concern about the potentially negative impact of skin cancer prevention on vitamin D status may undermine appropriate sun protective recommendations. Reading some educational resources was associated with confidence about vitamin D knowledge and a perception that significantly less summer sun exposure was required for those with high sun sensitivity to achieve adequate vitamin D, suggesting a potentially positive impact of such resources. Education could be targeted towards groups least likely to promote existing recommendations. Authoritative guidelines about vitamin D and sun protection would be a valued resource among GPs. Study findings are potentially valuable to help guide public policy and target interventions.     

The ABC of Vitamin D: A Qualitative Study of the Knowledge and Attitudes Regarding Vitamin D Deficiency amongst Selected Population Groups

Objective: In Australia, vitamin D supply in food is limited, and sun exposure is the main source of vitamin D. However skin cancer risk is high, and the need to gain some sun exposure for adequate vitamin D is challenging public health messages to use protection in the sun. The complex vitamin D public health message may be confusing the public and, in particular, those at highest risk for vitamin D deficiency. This study explored vitamin D and sun exposure attitudes, knowledge and practices of some groups considered at risk of vitamin D deficiency and those delivering healthy sun exposure messages to children. Method: 52 adults participated in six focus groups. Results: Results corroborated with previous research showing low levels of vitamin D knowledge. Individual and environmental barriers to receiving adequate sun exposure were also identified. Conclusions and Implications: The message advocating balanced sun exposure to produce adequate vitamin D needs to be made clearer and be more effectively communicated. Findings provide insights to aid development of appropriate public health messages for safe sun exposure and vitamin D, especially for vulnerable groups.     

儿童维生素D营养状况与心血管代谢异常关系的前瞻性队列研究

目的 探讨儿童中维生素D营养状况与心血管代谢异常发生的关系。方法 研究对象来自“儿童青少年心血管与骨健康促进项目”,于2017年采用分层整群抽样的方法在北京市对15 391名6~16岁儿童开展基线调查,2019年对其进行随访调查。采用log-binomial回归分析基线维生素D营养状况与随访期心血管代谢异常（肥胖、高血压、FPG升高和血脂异常）发病风险的关系。结果 共纳入10 482名研究对象,维生素D平均水平为（35.6±12.0）nmol/L,缺乏率为35.1%。随访期肥胖、高血压、FPG升高、高TC、高LDL-C、低HDL-C、高TG和高非HDL-C的2年累计发病率分别为4.3%、10.8%、8.5%、3.1%、2.5%、3.4%、2.5%和3.9%。控制相关潜在混杂因素后,与维生素D充足的儿童相比,维生素D缺乏和不足的儿童高TC［RR值（95% CI）：缺乏,2.06（1.19~3.58）;不足,2.80（1.61~4.89）］、高LDL-C［RR值（95% CI）：缺乏,1.67（1.02~2.73）;不足,1.99（1.19~3.33）］和高非HDL-C ［RR值（95% CI）：缺乏,2.00（1.26~3.17）;不足,2.45（1.53~3.92）］的发病风险增高,且随着维生素D水平的降低发病风险呈上升趋势（趋势性P<0.05）。按性别分层分析发现,维生素D缺乏与高TC［RR值（95% CI）：男童,2.64（1.19~5.87）;女童,3.13（1.43~6.83）］和高非HDL-C［RR值（95% CI）：男童,2.58（1.40~4.77）;女童,2.31（1.10~4.84）］的发生风险仍相关。结论 儿童期维生素D水平越低,TC、LDL-C和非HDL-C异常的发生风险越高。强调儿童维生素D的充足水平可能有助于心血管疾病的早期预防。     

Vitamin D Deficiency in Cord Plasma from Multiethnic Subjects Living in the Tropics

Background: Vitamin D deficiency is commonly reported in high-latitude areas and in dark-pigmented individuals. However, nothing is known about vitamin D in cord blood from multiethnic subjects living in the tropics.

Objective: Our study objective was to determine the prevalence of vitamin D deficiency in summer and winter in cord blood from multiethnic individuals in Hawai’i where sufficient sun irradiance occurs year-round for cutaneous vitamin D production.

Methods: 25-Hydroxyvitamin D (25(OH)D) levels were quantified by enzyme immunoassay in 100 cord plasma samples from apparently healthy full-term newborns and their mothers. Stratification was performed by birth season and ethnicity.

Results: Mean 25(OH)D levels were 24.5 ng/mL (9.1–68.3 ng/mL). Overall, 28% of samples were vitamin D deficient (<20 ng/mL) and 50% were insufficient (20–30 ng/mL). 25(OH)D levels (ng/mL) were highest in Caucasians (30.5, n = 19), followed by Asians (25.1, n = 43), Hispanics (21.5, n = 3), Pacific Islanders (20.0, n = 25), and African Americans (19.6, n = 2). Differences among groups were significant (p = 0.008). Cord plasmas from summer versus winter were higher overall (p = 0.001) and among Asians (p = 0.0003). Seasonal changes were correlated with sun irradiance overall (r = 0.43, p = 0.0001), among Caucasians (r = 0.45, p = 0.05), and among Asians (r = 0.45, p = 0.0001).

Conclusion: Our results suggest that prenatal supplement recommendations of 400 IU vitamin D/day do not protect against vitamin D deficiency, even in subjects living in the tropics where ample sun irradiance exists for cutaneous vitamin D synthesis. The high prevalence of vitamin D deficiency we observed emphasizes the necessity for regular 25(OH)D monitoring, particularly during pregnancy and lactation, in dark-pigmented individuals, and during winter months.     

The effect of vitamin D supplement on the score and quality of sleep in 20–50 year-old people with sleep disorders compared with control group

Objectives: Sleep quality may be directly related with vitamin D serum level. Some studies found that people with lower vitamin D serum level experienced a lower sleep quality. Consequently, this study aimed at determining the effect of vitamin D supplements on sleep score and quality in 20–50 year-old people with sleep disorders.

Methods: This double blind, clinical trial was performed in November 2015–February 2016 on 89 people with sleep disorders based on Petersburg's Sleep Index. Patient samples were divided randomly into two groups: intervention and placebo. At the end of the study, the data on 89 subjects (44 in intervention group and 45 people in placebo group) were examined. Intervention group received a 50?000-unit vitamin D supplement, one in a fortnight for 8 weeks. Meanwhile, placebo group received placebo. Before and after intervention, Petersburg's Sleep Quality Questionnaire, International Physical Activity Questionnaire, general information questionnaire, sun exposure, vitamin D serum level and 3-day food record questionnaire were assessed and recorded for all participants. To analyze data, t-test, chi square, ANCOVA, U-Mann–Whitney and Wilcoxon statistical tests were used.

Findings: Based on the results of the present study, at the end of the study sleep score (PSQI) reduced significantly in vitamin recipients as compared with placebo recipients (P?P?Conclusion: This study shows that the use of vitamin D supplement improves sleep quality, reduces sleep latency, raises sleep duration and improves subjective sleep quality in people of 20–50 year-old with sleep disorder.     

Risk factors for vitamin D deficiency in women aged 20–50 years consulting in general practice: a cross-sectional study

Abstract

Objective: Vitamin D deficiency is often unidentified, although treatment is simple and inexpensive. Our objective was to estimate the influence of concealing clothes and other risk factors for vitamin D deficiency in women aged 20 to 50 years consulting general practitioners. Methods: 13 GPs in the Rhone Alps area planned to recruit 300 women (100 veiled and 200 non-veiled) from January to March 2008. Serum 25(OH)D and PTH were measured in one single laboratory (Biomnis^®) by a radio-immunoassay method. A survey was administered about dietary habits, sun exposure, and quality of life. Results: Among 247 women enrolled, 196 were analysed: 61 wearing concealing clothes (31.2%) and 135 without (68.8%). As expected, 25(OH)D serum level was significantly lower in covered women (20.1 versus 38.9 nmol/l P < 0.001). Of women who did not wear concealing clothing, 39.3% had severe hypovitaminosis D (25(OH)D concentration < 30 nmol/l). Women wearing concealing clothes had more often other known risk factors such as dark skin (P < 0.001), less sunlight exposure, or a higher Body Mass Index (P = 0.009). Besides concealing clothing (OR 6.37, 95% CI: 1.35–30.09), multivariate analyses revealed two independent risk factors for vitamin D deficiency: no full-body sun exposure (OR: 3.06, 95% CI: 1.18–7.94) and no outdoor sports (OR: 2.81, 95% CI: 1.11–7.12) for threshold 52 nmol/l.

Conclusion: Young women consulting their GP had hypovitaminosis D more often than expected. Besides concealing clothing, absence of full body sun exposure during summer and of outdoor sports practice could suggest a possible vitamin D deficiency.     

Vitamin d beliefs and associations with sunburns, sun exposure, and sun protection

The main objective of this study was to examine certain beliefs about vitamin D and associations with sun exposure, sun protection behaviors, and sunburns. A total of 3,922 lifeguards, pool managers, and parents completed a survey in 2006 about beliefs regarding vitamin D and sun-related behaviors. Multivariate ordinal regression analyses and linear regression analysis were used to examine associations of beliefs and other variables. Results revealed that Non-Caucasian lifeguards and pool managers were less likely to agree that they needed to go out in the sun to get enough vitamin D. Lifeguards and parents who were non-Caucasian were less likely to report that sunlight helped the body to produce vitamin D. A stronger belief about the need to go out in the sun to get enough vitamin D predicted more sun exposure for lifeguards. For parents, a stronger belief that they can get enough vitamin D from foods predicted greater sun protection and a stronger belief that sunlight helps the body produce vitamin D predicted lower sun exposure. This study provides information regarding vitamin D beliefs and their association with certain sun related behaviors across different demographic groups that can inform education efforts about vitamin D and sun protection.     

Evaluation of the deficiency status of 25-hydroxyvitamin D and associated factors in Southwest China: A hospital-based retrospective cross-sectional analysis of a low-latitude,high-altitude,multiracial region

Vitamin D deficiency is widespread in different populations and regions worldwide and has become a global health issue. The vitamin D status of the population in the Yunnan Province of Southwest China has not been evaluated to date. Therefore, in this study, we evaluated the vitamin D status according to the serum concentrations of 25-hydroxyvitamin D (25(OH)D) in individuals of Yunnan Province, a low-latitude, high-altitude and multiracial region in China. The data on 25(OH)D concentrations from October 2012 to December 2017 were retrospectively collected and assessed using the laboratory information system from 52 950 hospital-based participants (age, 1 day–96 years; females, 73.74%). The serum concentration of 25(OH)D was evaluated using a chemiluminescent immunoassay. The analysis was stratified by sex, age, sampling season, testing year, minority, residential district, latitude, altitude and meteorological factors. Vitamin D status was classified as follows: severe deficiency: <10 ng/mL; deficiency: <20 ng/mL; insufficiency: <30 ng/mL; and sufficiency: ≥30 ng/mL. The results showed that vitamin D deficiency is highly prevalent in Yunnan Province in a hospital-based cohort, with a deficiency and severe deficiency rate of 65.1% and a sufficiency rate of 5.30%. Significantly lower vitamin D levels and sufficiency rates were observed in females than in males (20.13 ± 7.22 ng/mL vs. 17.56 ± 6.66 ng/mL and 8.20% vs. 4.20%; p < 0.01, respectively); in spring and winter (16.93 ± 6.24 ng/mL; 2.97% and 16.38 ± 6.43 ng/mL; 3.06%, respectively) than in summer and autumn (20.23 ± 7.14 ng/mL; 8.02% and 19.10 ± 6.97 ng/mL; 6.61% [p < 0.01], respectively); and in older individuals (0–6 years: 28.29 ± 13.13 ng/mL vs. >60 years: 14.88 ± 8.39 ng/mL; p < 0.01). Relatively higher vitamin D levels were observed in individuals of Yi, Zhuang, Hani, Dai, Miao and Lisu minorities and lower levels in individuals of Hui and Zang minorities compared with those of the Han nationality (p < 0.01). The mean sunlight duration, mean air temperature, maximum ultraviolet value and latitude were significantly correlated with vitamin D levels (r = −0.53, 0.60, 0.31, −0.68, respectively; p < 0.05). These results suggest that vitamin D status is influenced by sex, age, minority, latitude and some meteorological factors in areas with high and low altitudes. Hence, new public health policies, such as advice on sunshine exposure, food fortification and nutrition education, as well as the implementation of vitamin D supplementation programmes must be considered to alleviate vitamin D deficiency in Yunnan province, Southwest China.     

Sun protection and vitamin D status in an Australian subtropical community

Objective

Claims have been made that sun protection may negatively affect vitamin D status, but very few data are available about whether this applies to people in uncontrolled settings.

Method

In 1996 we measured 25(OH)-vitamin D concentrations in 1113 adults in Nambour, a subtropical community, who reported their concurrent sun protection behaviours in a skin cancer prevention trial. Estimates were adjusted for time outdoors, vitamin D intake and other factors known to affect vitamin D status.

Results

Persons who tended to stay in the shade had lower vitamin D levels than those who never stayed in the shade (62.5 vs. 68.8 nmol/L respectively, p = 0.01), and this association remained in persons who spent less than 50% (p = 0.02) but not in those who spent more than 50% of their time outdoors. Wearing a hat, long sleeves, sunglasses and use of sunscreen or umbrella were not associated with vitamin D status after adjustments, including after stratification by time outdoors.

Conclusion

Sun protection behaviour to reduce the risk of skin cancer can be maintained without affecting vitamin D serum status, although consistently seeking shade when spending less than 50% of daytime outdoors is associated with lower vitamin D levels.     

The Long Live Kids Campaign: Awareness of Campaign Messages

Media interventions are one strategy used to promote physical activity, but little is known about their effectiveness with children. As part of a larger evaluation, the purpose of this study was to assess the short-term effect of a private industry sponsored media literacy campaign, Long Live Kids, aimed at children in Canada. Specifically, we investigated children's awareness of the campaign and its correlates. Using a cohort design, a national sample (N = 331, male = 171; mean age = 10.81, SD = 0.99) completed a telephone survey two weeks prior to the campaign release, and again 1 year later. Only 3% of the children were able to recall the Long Live Kids campaign unprompted and 57% had prompted recall. Logistic regression found family income (Wald χ² = 11.06, p < .05), and free-time physical activity (Wald χ² = 5.67, p < .01) significantly predicted campaign awareness. Active children (≥3 days/week) were twice as likely to have recalled the campaign compared with inactive children (<3 days/week), whereas children living in high-income households (>$60,000/yr) were between 3.5 to 5 times more likely to have campaign recall compared with children living in a low-income households (<$20,000/yr). These findings suggest that media campaigns developed by industry may have a role in promoting physical activity to children although our findings identified a knowledge gap between children living in high- and low-income households. Future research needs to examine how children become aware of such media campaigns and how this mediated information is being used by children.     

The high prevalence of vitamin D insufficiency across Australian populations is only partly explained by season and latitude

BACKGROUND: Inadequate sun exposure and dietary vitamin D intake can result in vitamin D insufficiency. However, limited data are available on actual vitamin D status and predictors in healthy individuals in different regions and by season. METHODS: We compared vitamin D status [25-hydroxyvitamin D; 25(OH)D] in people < 60 years of age using data from cross-sectional studies of three regions across Australia: southeast Queensland (27 degrees S; 167 females and 211 males), Geelong region (38 degrees S; 561 females), and Tasmania (43 degrees S; 432 females and 298 males). RESULTS: The prevalence of vitamin D insufficiency (相似文献   

Examining Differences in Audience Recall and Reaction Between Mediated Portrayals of Mental Illness as Trivializing Versus Stigmatizing

Researchers have documented the ways in which media stigmatize mental illness. However, media also portray mental illness trivially when diseases are mocked, oversimplified, shown to be less severe than in actuality, or represented as beneficial to an individual. Trivialization of mental illnesses could potentially lead audiences to be less likely to seek help or less likely to support related policy efforts. Therefore, it is important to understand how audiences recall and react to stigmatizing and trivializing mental illness portrayals. An experiment (N = 175) asked participants to recall either a media portrayal where mental illness was stigmatized or a portrayal where it was trivialized. Results suggest that audiences recall certain components of stigmatization and trivialization better than others. And, recollections of trivialization were associated with different patterns of word use than stigmatization. A second experiment (N = 141) found similar patterns when showing participants specific examples of different mental illness portrayals and asking them to immediately recall the content. Overall, these results suggest that theory and conceptual models about the nature and effects of mental illness portrayals could be updated to include both stigmatization and trivialization.     

Vitamin D Deficiency in Pregnant Ukrainian Women: Effects of Alcohol Consumption on Vitamin D Status

Objective: Heavy alcohol consumption can alter vitamin D status; however, the relationships between alcohol consumption and vitamin D concentrations in pregnant women have not been well studied. The aim of this study was to investigate the vitamin D status in a population of alcohol-exposed (N = 180) and low/unexposed control (N = 179) Ukrainian pregnant women.

Methods: Women who attended prenatal care facilities in 2 regions of Ukraine (Rivne and Khmelnytsky) for a routine prenatal visit were screened for the study. At the time of enrollment (20.4 ± 7.0 weeks of gestation), blood samples and alcohol consumption data (during a typical week around conception and the most recent 2 weeks) were collected. Vitamin D status was assessed by 25-hydroxyvitamin D [25(OH)D] concentrations.

Results: A high prevalence of suboptimal vitamin D status in pregnant Ukrainian women was observed. Overall, 50.1% and 33.4% of the women were classified as vitamin D deficient [25(OH)D < 20 ng/mL] or insufficient [25(OH)D ≥ 20 ng/mL and ≤30 ng/mL], respectively, based on 2011 Endocrine Society guidelines. Alcohol-exposed women had significantly lower 25(OH)D concentrations than low/unexposed women in Spring (p = 0.006) and Winter (p = 0.022). When vitamin D concentrations were grouped into sunny season (Summer + Fall) compared to not sunny season (Winter + Spring), there was a significant ethanol by season interaction (p = 0.0028), with alcohol-drinking women having lower circulating vitamin D compared to low/unexposed women in seasons of low sun availability.

Conclusions: These data suggest that when vitamin D concentrations are generally low (e.g., during seasons of low sun availability), alcohol consumption during pregnancy has a negative impact on vitamin D status.     

Vitamin D insufficiency in southern Arizona

BACKGROUND: Vitamin D deficiency or insufficiency has been observed among populations in the northern United States. However, data on the prevalence of vitamin D deficiency in areas of high sun exposure, such as Arizona, are limited. OBJECTIVE: The purpose of this study was to analyze serum 25-hydroxyvitamin D [25(OH)D] concentrations in residents of southern Arizona and to evaluate predictors of 25(OH)D in this population. DESIGN: Cross-sectional analyses of serum from participants in a colorectal adenoma prevention study were conducted to determine rates of vitamin D deficiency. Participants were categorized into 4 groups on the basis of serum 25(OH)D concentrations: <10.0 ng/mL, > or =10.0 ng/mL and <20.0 ng/mL, > or =20.0 ng/mL and <30.0 ng/mL, and > or =30.0 ng/mL. RESULTS: The mean serum 25(OH)D concentration for the total population was 26.1 +/- 9.1 ng/mL. Of 637 participants, 22.3% had 25(OH)D concentrations >30 ng/mL, 25.4% had concentrations <20 ng/mL, and 2.0% had concentrations <10 ng/mL. Blacks (55.5%) and Hispanics (37.6%) were more likely to have deficient 25(OH)D concentrations (<20 ng/mL) than were non-Hispanic whites (22.7%). Sun exposure had a greater effect on 25(OH)D in whites than in blacks and Hispanics, whereas BMI appeared to be more important in the latter groups. CONCLUSION: Despite residing in a region with high chronic sun exposure, adults in southern Arizona are commonly deficient in vitamin D deficiency, particularly blacks and Hispanics.     

Vitamin D status affects strength gains in older adults supplemented with a combination of β-hydroxy-β-methylbutyrate, arginine, and lysine: a cohort study

Background: Older adults supplemented for 1 year with β‐hydroxy‐β‐methylbutyrate, arginine, and lysine (HMB/ARG/LYS) were previously shown to have significant gains in fat‐free mass (FFM) but not muscular strength. Objective: Recently, increasing levels of serum vitamin D have been associated with an increase in muscle function, particularly in the elderly. To determine if vitamin D status may have limited strength gain in participants supplemented with HMB/ARG/LYS, the authors performed post hoc analysis of strength based on the participants' vitamin D status. Methods: Elderly (age 76.0 ± 1.6 years) adults were recruited for a double‐blinded, controlled study and were randomly assigned to either an isonitrogenous control (n = 37) or HMB/ARG/LYS (n = 40) for the yearlong study. Participants were further segregated based on their vitamin D status of either <30 or ≥30 ng 25OH‐vitD₃/mL serum, and an analysis was performed on the 4 cohorts. Results: Regardless of vitamin D status, HMB/ARG/LYS resulted in significantly increased FFM (P < .02), but only in those with vitamin D status ≥30 ng 25OH‐vitD₃/mL was there a significant increase in strength with HMB/ARG/LYS (P < .01). Control‐supplemented participants, regardless of vitamin D status, and the HMB/ARG/LYS‐supplemented participants with vitamin D status <30 ng 25OH‐vitD₃ failed to show improvements in strength. Conclusions: The nutrient cocktail of HMB/ARG/LYS alone was effective in increasing muscle mass regardless of vitamin D status, but accompanying strength increases were observed only when participants also had adequate vitamin D status indicating a synergistic effect between the HMB/ARG/LYS and vitamin D.     

Optimizing the Presentation of Mental Health Information in Social Media: The Effects of Health Testimonials and Platform on Source Perceptions,Message Processing,and Health Outcomes

Using social media for the purpose of disseminating mental health information is a critical area of scientific inquiry for health communication professionals. The purpose of this study was to investigate whether the presence of a first-person testimonial in educational mental health information placed in Facebook and Twitter messages influenced college students’ (N = 257) source perceptions, information processing, cognitive elaboration, health information recall, beliefs, and behavioral intentions. Results show that exposure to social media messages that featured mental health information embedded with a testimonial predicted less source homophily and more critical thoughts about the social media source, less systematic message processing, and less cognitive elaboration. Health information recall was significantly impacted by both the social media platform and message content such that participants in the testimonial condition on Facebook were more likely to recall the health facts in those messages whereas participants who viewed the testimonial in Twitter were less likely to recall the facts in those tweets. Compared to those who read Facebook messages, participants who read Twitter messages reported higher levels of systematic message processing. These findings suggest that the integration of health testimonials into social media messages might inadvertently provoke psychological resistance to mental health information, thereby reducing the persuasive impact of those messages.     

Effect of Vitamin D Supplementation on Depressive Symptoms in Patients With Knee Osteoarthritis

ObjectivesTo determine the effect of vitamin D supplementation and maintaining sufficient serum vitamin D on depressive symptoms in patients with knee osteoarthritis (OA) and vitamin D deficiency.DesignA prespecified secondary analysis of a multicentre, randomized, double-blind, placebo-controlled trial. Participants were randomly assigned to receive oral vitamin D₃ (50,000 IU, n = 209) or placebo (n = 204) monthly for 24 months. In addition, participants who completed the trial were classified into 2 groups according to their serum 25(OH)D levels at month 3 and 24 as follows: not consistently sufficient (serum 25(OH)D ≤ 50 nmol/L at month 3 and/or 24), and consistently sufficient (serum 25(OH)D > 50 nmol/L at both month 3 and 24). Multilevel mixed-effect models were used to compare differences of change in PHQ-9 scores between groups.Setting and ParticipantsThis clinical trial was conducted in participants with symptomatic knee OA and vitamin D deficiency from June 2010 to December 2013 in Tasmania and Victoria, Australia.MeasuresThe primary outcome was the depressive symptoms change over 24 months, which was measured using the Patient Health Questionnaire (PHQ-9, 0-27).ResultsOf 599 participants who were screened for eligibility, 413 participants were enrolled (mean age: 63.2 years; 50.3% female) and 340 participants (intervention n = 181, placebo n = 159, 82.3% retention rate) completed the study. The baseline prevalence of depression (PHQ-9 score ≥5) was 25.4%. Depressive symptoms improved more in the vitamin D supplementation group compared to the placebo group [β: ?0.66, 95% confidence interval (CI): ?1.22 to ?0.11, P for difference = .02] and in the participants who maintained vitamin D sufficiency compared to those who did not (β: ?0.73, 95% CI: ?1.41 to ?0.05, P for difference = .04) over 24 months.Conclusions/ImplicationsThese findings suggest that vitamin D supplementation and maintaining adequate vitamin D levels over 24 months may be beneficial for depressive symptoms in patients with knee OA.