Discussing diet, nutrition, and body weight after treatment for gynecological cancer: a conversation analytic study of outpatient consultations

PURPOSE

To generate direct observational evidence for understanding how diet, nutrition, and weight-related topics are discussed during follow-up after treatment for gynecological cancer, as recommended by survivorship care guidelines.

METHODS

Conversation analysis of 30 audio-recorded outpatient consultations, involving 4 gyne-oncologists, 30 women who had completed treatment for ovarian or endometrial cancer, and 11 family members/friends.

RESULTS

From 21 instances in 18 consultations, diet, nutrition, or weight-related talk continued beyond initiation if the issue raised was ostensibly relevant to the clinical activity being undertaken at the time. These instances led to care-related outcomes (i.e., general dietary recommendations, referral to support, behavior change counseling) only when the patient identified needing further support. Diet, nutrition, or weight-related talk was not continued by the clinician if it was not apparently related to the current clinical activity.

CONCLUSIONS

The continuation of diet, nutrition, or weight-related talk during outpatient consultations after treatment for gynecological cancer, and the subsequent delivery of care-related outcomes, depends on its immediate clinical relevance and the patient indicating needing further support. The contingent nature of these discussions means there can be missed opportunities for the provision of dietary information and support post-treatment.

IMPLICATIONS FOR CANCER SURVIVORS

If seeking information or support for diet, nutrition, or weight-related issues post-treatment, cancer survivors may need to be explicit regarding their need for this during outpatient follow-up. Additional avenues for dietary needs assessment and referral should be considered to optimize the consistent delivery of diet, nutrition, and weight-related information and support after treatment for gynecological cancer.

Inflammatory potential of diet and mortality in Australian adults

OBJECTIVE

Inflammation is implicated in chronic diseases including cancer and cardiovascular diseases (CVD), which are major causes of mortality. Diet can influence inflammation status. We therefore examined whether the inflammatory potential of a person's diet is associated with mortality.

DESIGN

Inflammatory potential of usual diet was assessed by calculating dietary inflammatory index (DII) scores from repeated food frequency (FFQ) data (collected in 1992, 1994, 1996), placing each participant's diet on a continuum from anti- to pro-inflammatory. DII scores were analysed as a continuous variable and as categories by creating quartile groups. Death registry data were used to ascertain all-cause mortality and separately mortality from CVD, cancers, and other causes between 1992-2022. Cox proportional hazards regression analysis was used to calculate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs), comparing higher vs. lowest quartile groups, or HR change per one DII-unit increase.

SETTING

Nambour, Australia.

PARTICIPANTS

A community-based sample of 1440 adults aged 25-75 years.

RESULTS

During follow-up, 488 participants died, including 188 from CVD, 151 from cancer, and 170 from other causes. Participants in the most pro-inflammatory diet group were at increased risk of all-cause mortality (HRQ4vsQ1 = 1.55; 95% CI 1.19, 2.03; P trend < 0.001), and other-cause mortality (HRQ4vsQ1 = 1.69; 95% CI 1.12, 2.54; P trend 0.01). A one-unit increase in DII-score was associated with a 36% increased risk of CVD among those younger than 55 years of age (HR for a one-unit increase in DII score: 1.36, 95% CI: 1.04-1.78). The risk of cancer mortality was also increased for those with a more pro-inflammatory diet in age ≤55yr: HR for a one-unit increase in DII score: 1.20, 95% CI: 1.02-1.40, and age 56-65yr: HR for a one-unit increase in DII score: 1.11, 95 % CI: 1.00-1.23).

CONCLUSIONS

A pro-inflammatory diet increases the risk of all-cause mortality. Our results support promotion of anti-inflammatory diets to help promote longevity.

The effect of three years of vitamin D supplementation on erectile dysfunction: Results from the randomized placebo-controlled D-Health Trial

BACKGROUND & AIMS

Erectile dysfunction is common among older men and has been associated with low serum 25-hydroxy vitamin D concentration. However, this association may be due to uncontrolled confounding, and there is a paucity of evidence from interventional studies. We aimed to examine the effect of vitamin D supplementation on the prevalence of erectile dysfunction, in an exploratory analysis using data from a large randomized controlled trial.

METHODS

The D-Health Trial recruited Australians aged 60-84 years between January 2014 and May 2015 and randomly assigned them to supplementation with 60,000 IU of vitamin D or placebo per month for up to 5 years. Blood samples were collected annually from randomly selected participants (total N = 3943). We assessed erectile dysfunction at the end of the third year of follow-up. We used log-binomial regression to examine the effect of vitamin D on the prevalence of erectile dysfunction overall, and within sub-groups.

RESULTS

Of the 11,530 men enrolled, 8920 (77.4 %) completed the erectile dysfunction question and were included in the analysis. After three years of supplementation, the mean serum 25-hydroxy vitamin D concentration was 76 nmol/L (standard deviation (SD) 24.94) in the placebo group and 106 nmol/L (SD 26.76) in the vitamin D group (p < 0.0001). The prevalence of erectile dysfunction was 58.8 % and 59.0 % in the vitamin D and placebo groups, respectively (prevalence ratio 1.00, 95 % CI 0.97, 1.03); there was no evidence of an effect of vitamin D in any subgroup analyses.

CONCLUSION

Supplementing older men with vitamin D is unlikely to prevent or improve erectile dysfunction.

CLINICAL TRIALS REGISTRY

(ACTRN12613000743763).

A Double-Blind Randomised Controlled Trial of Prebiotic Supplementation in Children with Autism: Effects on Parental Quality of Life, Child Behaviour, Gastrointestinal Symptoms, and the Microbiome

PURPOSE

Modifying gut bacteria in children with autism may influence behaviour, with potential to improve family functioning. We conducted a randomised controlled trial to assess the effect of prebiotics on behaviour, gastrointestinal symptoms and downstream effects on parental quality of life.

METHOD

Children with autism (4-10yrs) were randomised to 2.4 g/d of prebiotic (GOS) or placebo for six weeks. Pre and post stools samples were collected, and validated questionnaires used to measure change in social and mealtime behaviours, GI symptoms and pQOL. Linear mixed models evaluated group differences for behavioural variables, and Mann Whitney U tests were used to compare change between-groups for GI symptoms, differential abundance of genera and alpha diversity of the microbiome.

RESULTS

Thirty-three parent-child dyads completed the trial. No group difference was seen for behavioural variables but both groups improved significantly from baseline. There was a medium effect size between groups for GI symptoms (d = 0.47) and pQOL (d = 0.44) driven by greater improvements in the prebiotic group. Bifidobacterium increased threefold following prebiotics (1.4-5.9%, p < 0.001) with no change in controls. Supplements were well tolerated, compliance with dose 94%.

CONCLUSION

Prebiotics modify levels of Bifidobacterium and prove well tolerated but in this instance, resulted in only marginal effects on GI symptoms and pQOL. A larger sample of children with more severe symptoms could help to determine the potential of prebiotics in autism.

TRIAL REGISTRATION

https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12619000615189 .

Mental health and diet quality after primary treatment for ovarian cancer

AIMS

To investigate anxiety and depression after primary treatment for ovarian cancer in relation to diet quality and intake.

METHODS

In a cohort of women with ovarian cancer in Australia, levels of anxiety and depression (normal, subclinical, and clinical) were assessed using the Hospital Anxiety and Depression Scale at 9 months post-diagnosis. Dietary intake was assessed using a validated food frequency questionnaire at 12 months post-diagnosis and scored using the Healthy Eating Index 2015. Multinomial logistic regression and bivariate analyses were used to investigate relationships between levels of anxiety and depression and subsequent diet quality and intake of food groups.

RESULTS

Of 595 women, anxiety and depression were identified among 128 (21%) and 80 (13%) women, respectively. Compared to women without anxiety or depression, women with subclinical anxiety (odds ratio = 0.49, 95% confidence interval: 0.25-0.98) and those with clinical depression (odds ratio = 0.25, 95% confidence interval: 0.07-0.93) were less likely to score in the highest quartile for diet quality. Separate adjustment for age, education, employment, disease stage, body mass index, and smoking status did not attenuate these associations. In bivariate analyses, women with subclinical anxiety were more likely to report higher intakes of sweet foods. Those with clinical depression were more likely to report lower intakes of orange vegetables and wholegrains, higher intakes of sweetened beverages, and not consume alcohol or soya foods.

CONCLUSIONS

Anxiety or depression after primary treatment for ovarian cancer may be associated with poorer diet quality. Efforts to improve diet quality post-treatment should consider support for mental health.

The Effect of Vitamin D Supplementation on Hypothyroidism in the Randomized Controlled D-Health Trial

Background: Hypothyroidism is common, and in iodine-sufficient areas, it is primarily caused by autoimmune destruction of the thyroid gland. Observational studies have consistently shown an inverse association between serum 25-hydroxyvitamin D concentration and autoimmune diseases; however, there is a lack of evidence from randomized controlled trials to support a benefit of vitamin D supplementation, particularly for autoimmune thyroid diseases. We, therefore, aimed to assess the effect of vitamin D supplementation on the incidence of hypothyroidism. Methods: We analyzed data from the D-Health Trial (n = 21,315), a randomized double-blind placebo-controlled trial of 60,000 international units per month of supplemental vitamin D3 among Australians aged 60 years and over. Hypothyroidism, a tertiary outcome of the D-Health Trial, was defined by treatment with levothyroxine, ascertained through linkage with the Australian Pharmaceutical Benefits Scheme. The outcome was time to first prescription of levothyroxine. We began follow-up at 12 months after randomization; people who had died or who had been dispensed levothyroxine during the first year were excluded. Flexible parametric survival models were used to assess the effect of vitamin D supplementation on hypothyroidism, overall and within strata defined by age, sex, body mass index, and predicted baseline vitamin D status. Results: We included 17,851 participants in the main analysis (vitamin D = 8939; placebo = 8912). During a median follow-up of 4.1 years (interquartile range 4.1-4.1), 293 participants developed hypothyroidism (vitamin D = 138 [1.5%]; placebo = 155 [1.7%]). Vitamin D supplementation did not significantly reduce the incidence of hypothyroidism (overall hazard ratio [HR] 0.89; 95% confidence interval [CI] 0.71-1.12). There was some suggestion of an effect in females (overall HR 0.78; CI 0.58-1.06) but not in males (overall HR 1.06; CI 0.74-1.50; p interaction 0.20). Conclusions: Vitamin D supplementation did not reduce the incidence of hypothyroidism overall; however, the possible beneficial effect observed in females warrants further investigation. Clinical Trial Registration: Australian New Zealand Clinical Trials Registry: ACTRN12613000743763.

Vitamin D supplementation and major cardiovascular events: D-Health randomised controlled trial

OBJECTIVE

To investigate whether supplementing older adults with monthly doses of vitamin D alters the incidence of major cardiovascular events.

DESIGN

Randomised, double blind, placebo controlled trial of monthly vitamin D (the D-Health Trial). Computer generated permuted block randomisation was used to allocate treatments.

SETTING

Australia from 2014 to 2020.

PARTICIPANTS

21 315 participants aged 60-84 years at enrolment. Exclusion criteria were self-reported hypercalcaemia, hyperparathyroidism, kidney stones, osteomalacia, sarcoidosis, taking >500 IU/day supplemental vitamin D, or unable to give consent because of language or cognitive impairment.

INTERVENTION

60 000 IU/month vitamin D₃ (n=10 662) or placebo (n=10 653) taken orally for up to five years. 16 882 participants completed the intervention period: placebo 8270 (77.6%); vitamin D 8552 (80.2%).

MAIN OUTCOME MEASURES

The main outcome for this analysis was the occurrence of a major cardiovascular event, including myocardial infarction, stroke, and coronary revascularisation, determined through linkage with administrative datasets. Each event was analysed separately as secondary outcomes. Flexible parametric survival models were used to estimate hazard ratios and 95% confidence intervals.

RESULTS

21 302 people were included in the analysis. The median intervention period was five years. 1336 participants experienced a major cardiovascular event (placebo 699 (6.6%); vitamin D 637 (6.0%)). The rate of major cardiovascular events was lower in the vitamin D group than in the placebo group (hazard ratio 0.91, 95% confidence interval 0.81 to 1.01), especially among those who were taking cardiovascular drugs at baseline (0.84, 0.74 to 0.97; P for interaction=0.12), although the P value for interaction was not significant (<0.05). Overall, the difference in standardised cause specific cumulative incidence at five years was -5.8 events per 1000 participants (95% confidence interval -12.2 to 0.5 per 1000 participants), resulting in a number needed to treat to avoid one major cardiovascular event of 172. The rate of myocardial infarction (hazard ratio 0.81, 95% confidence interval 0.67 to 0.98) and coronary revascularisation (0.89, 0.78 to 1.01) was lower in the vitamin D group, but there was no difference in the rate of stroke (0.99, 0.80 to 1.23).

CONCLUSIONS

Vitamin D supplementation might reduce the incidence of major cardiovascular events, although the absolute risk difference was small and the confidence interval was consistent with a null finding. These findings could prompt further evaluation of the role of vitamin D supplementation, particularly in people taking drugs for prevention or treatment of cardiovascular disease.

TRIAL REGISTRATION

ACTRN12613000743763.

Vitamin D supplementation and cognition-Results from analyses of the D-Health trial

BACKGROUND

Observational studies have consistently found a link between low serum 25-hydroxyvitamin D concentration and higher risk of cognitive impairment. Results from randomized controlled trials have been mixed, and few have been conducted in the general population.

METHODS

We recruited 21,315 community-dwelling Australians aged between 60 and 84 years to participate in the D-Health Trial, a randomized, double-blind, placebo-controlled trial. The intervention was monthly oral doses of 60,000 international units of vitamin D or placebo for 5 years. We assessed cognitive function in a randomly sampled group of participants aged ≥70 years using the Telephone Interview for Cognitive Status (TICS) at 2 and 5 years after randomization. The primary outcome for this analysis was TICS score; the secondary outcome was the proportion of people who had cognitive impairment (defined as TICS score ≤25). We analyzed data using mixed models (linear and logistic).

RESULTS

We interviewed 3887 participants at year 2 and 3614 participants at year 5. The mean TICS score at these time points was 32.3 and 32.2, respectively. Vitamin D supplementation did not affect cognitive function as measured by TICS score (mean difference between vitamin D and placebo groups 0.04; 95% CI -0.14 to 0.23), or alter risk of cognitive impairment (odds ratio 1.00; 95% CI 0.75 to 1.33).

CONCLUSIONS

Monthly bolus doses of vitamin D supplementation neither enhanced nor hindered cognitive function among older adults. Population-wide vitamin D supplementation of older adults that are largely vitamin D replete is unlikely to substantially benefit cognition.

Association of protein intake with recurrence and survival following primary treatment of ovarian cancer

BACKGROUND

Malnutrition is common during treatment for ovarian cancer and one in three report multiple symptoms affecting food intake after primary treatment. Little is known about diet post-treatment in relation to ovarian cancer survival, however, general recommendations for cancer survivors are to maintain a higher level of protein intake to support recovery and minimize nutritional deficits.

OBJECTIVE

To investigate whether intake of protein and protein food sources following primary treatment for ovarian cancer is associated with recurrence and survival.

DESIGN

Intake levels of protein and protein food groups were calculated from dietary data collected about 12 months post-diagnosis using a validated food frequency questionnaire in an Australian cohort of females with invasive epithelial ovarian cancer. Disease recurrence and survival status were abstracted from medical records (median 4.9 years follow-up). Cox proportional hazards regression was used to calculate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for protein intake and progression-free and overall survival.

RESULTS

Among 591 females who were progression-free at 12-months follow-up, 329 (56%) subsequently experienced cancer recurrence and 231 (39%) died. A higher level of protein intake was associated with better progression-free survival (>1-1.5 vs. ≤1 grams per kilogram body weight (g/kg): HR_adjusted=0.69, 95% CI 0.48, 1.00; >1.5 vs. ≤1g/kg: HR_adjusted=0.61, 95% CI 0.41, 0.90; >20% vs. ≤20% total energy intake from protein: HR_adjusted=0.77, 95% CI 0.61, 0.96). There was no evidence for better progression-free survival with any particular protein food sources. There was a suggestion of better overall survival among those with higher total intakes of animal-based protein foods, particularly dairy products (HR=0.71, 95% CI 0.51, 0.99 for highest vs. lowest tertiles of total dairy intake).

CONCLUSIONS

After primary treatment for ovarian cancer, a higher level of protein intake may benefit progression-free survival. Ovarian cancer survivors should avoid dietary practices that limit intake of protein-rich foods.

The effect of monthly vitamin D supplementation on fractures: a tertiary outcome from the population-based, double-blind, randomised, placebo-controlled D-Health trial

BACKGROUND

Low serum 25-hydroxy vitamin D concentration is associated with increased fracture risk. It is uncertain whether vitamin D supplementation reduces fractures, or whether intermittent doses are harmful. We aimed to investigate if supplementing adults living in Australia with monthly doses of 60 000 international units (IU) vitamin D₃ for 5 years or less altered the rate of fractures.

METHODS

We did a population-based, double-blind, randomised, placebo-controlled trial of oral vitamin D₃ supplementation (60 000 IU per month) for up to 5 years in adults aged 60-84 years living in Australia. We randomly assigned (1:1) 21 315 participants to either vitamin D or placebo. We ascertained fractures through linkage with administrative datasets. The main outcome was total fractures. Additional outcomes were non-vertebral, major osteoporotic (hip, wrist, proximal humerus, and spine), and hip fractures. We excluded participants (989 [4·6%]) without linked data, and estimated hazard ratios (HRs) and 95% CIs using flexible parametric survival models. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000743763, and the trial intervention ended in February, 2020.

FINDINGS

Between Feb 14, 2014, and June 17, 2015, we recruited 21 315 participants. For the current analysis, we included 20 326 participants (vitamin D 10 154 [50·0%]; placebo 10 172 [50·0%]). 9295 (45·7%) of 20 326 participants were women and the mean age was 69·3 years (SD 5·5). Over a median follow-up of 5·1 years (IQR 5·1-5·1), 568 (5·6%) participants in the vitamin D group and 603 (5·9%) in the placebo group had one or more fractures. There was no effect on fracture risk overall (HR 0·94 [95% CI 0·84-1·06]), and the interaction between randomisation group and time was not significant (p=0·14). However, the HR for total fractures appeared to decrease with increasing follow-up time. The overall HRs for non-vertebral, major osteoporotic, and hip fractures were 0·96 (95% CI 0·85-1·08), 1·00 (0·85-1·18), and 1·11 (0·86-1·45), respectively.

INTERPRETATION

These findings do not support concerns that bolus doses of vitamin D administered monthly increase fracture risk. Long-term supplementation might reduce the incidence of total fractures, but additional research is needed to clarify this effect.

FUNDING

Australian National Health and Medical Research Council.

Vitamin D Supplementation and the Incidence of Cataract Surgery in Older Australian Adults

PURPOSE

Observational studies suggest that higher serum 25-hydroxy vitamin D (25(OH)D) concentration may be associated with lower risk of cataract. However, no randomized controlled trials have assessed the effect of vitamin D supplementation on the incidence of cataract. We aimed to assess whether vitamin D supplementation reduces the incidence of cataract surgery.

DESIGN

We conducted an ancillary study of the D-Health Trial, a randomized, double-masked, placebo-controlled trial of monthly vitamin D conducted from 2014 through 2020 within the Australian general population.

PARTICIPANTS

We invited 421 207 men and women 60 to 84 years of age to participate; including an additional 1896 volunteers, 40 824 expressed interest. Those with hypercalcemia, hyperparathyroidism, kidney stones, osteomalacia, or sarcoidosis or those who were taking more than 500 international units (IU) supplemental vitamin D per day were excluded. A total of 21 315 were randomized, and 1390 participants did not fulfil the eligibility criteria for this analysis (linked data available, no cataract within first 6 months), leaving 19 925 included. The median follow-up was 5 years.

METHODS

Participants took 60 000 IU of vitamin D₃ (n = 10 662) or placebo (n = 10 653) orally once per month for a maximum of 5 years.

MAIN OUTCOME MEASURES

The primary outcome for this analysis was the first surgical treatment for cataract, ascertained through linkage to universal health insurance records and hospital data.

RESULTS

Among 19 925 participants eligible for this analysis (mean age, 69.3 years; 46% women) 3668 participants (18.4%) underwent cataract surgery during follow-up (vitamin D: n = 1841 [18.5%]; placebo: n = 1827 [18.3%] ). The incidence of cataract surgery was similar between the two groups (incidence rate, 41.6 and 41.1 per 1000 person-years in the vitamin D and placebo groups, respectively; hazard ratio, 1.02; 95% confidence interval, 0.95-1.09). In prespecified subgroup analyses, the effect of vitamin D supplementation on the incidence of cataract surgery was not modified by age, sex, body mass index, predicted serum 25(OH)D concentration, or ambient ultraviolet radiation.

CONCLUSIONS

Routinely supplementing older adults who live in an area with a low prevalence of vitamin D deficiency with high-dose vitamin D is unlikely to reduce the need for cataract surgery.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Vitamin D supplementation and hospitalization for infection in older adults: A post-hoc analysis of data from the Australian D-Health Trial

BACKGROUND

Evidence suggests that vitamin D influences the immune system. Recent studies indicate that vitamin D supplementation may reduce the severity of infections, but this has not been confirmed.

OBJECTIVES

The objective of this study was to assess the effect of vitamin D supplementation on hospitalization for infection.

METHODS

The D-Health Trial was a randomized, double-blind, placebo-controlled trial of monthly 60,000 international units of vitamin D₃ for 5 y among 21,315 Australians aged 60-84 y. Hospitalization for infection, ascertained through linkage with hospital admitted patient data, is a tertiary outcome of the trial. The primary outcome for this post-hoc analysis was hospitalization for any infection. Secondary outcomes were extended hospitalization for infection (length of stay >3 d and >6 d) and hospitalization for respiratory tract, skin, and gastrointestinal infections. We used negative binomial regression to estimate the effect of vitamin D supplementation on outcomes.

RESULTS

Participants (46% women, mean age: 69 y), were followed up for a median of 5 y. Vitamin D supplementation had little or no effect on the incidence of hospitalization for any infection [incidence rate ratio (IRR): 0.95; 95% CI: 0.86, 1.05], respiratory tract (IRR: 0.93; 95% CI: 0.81, 1.08), skin (IRR: 0.95; 95% CI: 0.76, 1.20), gastrointestinal infections (IRR: 1.03; 95% CI: 0.84, 1.26), or hospitalizations lasting >3 d (IRR: 0.94; 95% CI: 0.81, 1.09), with all CIs consistent with a null finding. People supplemented with vitamin D had fewer hospitalizations lasting >6 d (IRR: 0.80; 95% CI: 0.65, 0.99).

CONCLUSIONS

We did not find a protective effect of vitamin D on hospitalization for infection, but it reduced the number of extended hospitalizations. In populations where few people are vitamin D deficient, the effect of population-wide supplementation is likely to be small, but these findings support previous studies suggesting that vitamin D plays a role in infectious disease. The D-Health Trial is registered at the Australian New Zealand Clinical Trials Registry as ACTRN12613000743763.

The effect of vitamin D supplementation on the gut microbiome in older Australians - Results from analyses of the D-Health Trial

Observational studies suggest a link between vitamin D and the composition of the gut microbiome, but there is little evidence from randomized controlled trials of vitamin D supplementation. We analyzed data from the D-Health Trial, a randomized, double-blind, placebo-controlled trial. We recruited 21,315 Australians aged 60-84 y and randomized them to 60,000 IU of vitamin D₃ or placebo monthly for 5 y. Stool samples were collected from a sample of 835 participants (417 in the placebo and 418 in the vitamin D group) approximately 5 y after randomization. We characterized the gut microbiome using 16S rRNA gene sequencing. We used linear regression to compare alpha diversity indices (i.e. Shannon index (primary outcome), richness, inverse Simpson index), and the ratio of Firmicutes to Bacteroidetes between the two groups. We analyzed between-sample (beta) diversity (i.e. Bray Curtis distance and UniFrac index) using principal coordinate analysis and used PERMANOVA to test for significant clustering according to randomization group. We also assessed the difference in the abundance of the 20 most abundant genera between the two groups using negative binomial regression model with adjustment for multiple testing. Approximately half the participants included in this analysis were women (mean age 69.4 y). Vitamin D supplementation did not alter the Shannon diversity index (mean 3.51 versus 3.52 in the placebo and vitamin D groups, respectively, p = 0.50). Similarly, there was little difference between the groups for other alpha diversity indices, the abundance of different genera, and the Firmicutes-to-Bacteroidetes ratio. We did not observe clustering of bacterial communities according to randomization group. In conlusion, monthly doses of 60,000 IU of vitamin D supplementation for 5 y did not alter the composition of the gut microbiome in older Australians.

Effect of vitamin D supplementation on depression in older Australian adults

OBJECTIVES

To investigate whether vitamin D supplementation reduces depressive symptoms and incidence of antidepressant use.

METHODS

We used data from the D-Health Trial (N = 21,315), a randomized double-blind placebo-controlled trial of monthly vitamin D₃ for the prevention of all-cause mortality. Participants were Australians aged 60-84 years. Participants completed the Patient Health Questionnaire (PHQ-9) at 1, 2 and 5 years after randomization to measure depressive symptoms; national prescribing records were used to capture antidepressant use. We used mixed models and survival models.

RESULTS

Analyses of PHQ-9 scores included 20,487 participants (mean age 69·3 years, 46% women); the mean difference (MD) in PHQ-9 score (vitamin D vs. placebo) was 0·02 (95% CI -0·06, 0·11). There was negligible difference in the prevalence of clinically relevant depression (PHQ-9 score ≥10) (odds ratio 0·99; 95% CI 0·90, 1·08). We included 16,670 participants in the analyses of incident antidepressant use (mean age 69·4 years, 43% women). Incidence of antidepressant use was similar between the groups (hazard ratio [HR] 1·04; 95% CI 0·96, 1·12). In subgroup analyses, vitamin D improved PHQ-9 scores in those taking antidepressants at baseline (MD -0·25; 95% CI -0·49, -0·01; p-interaction = 0·02). It decreased risk of antidepressant use in participants with predicted 25(OH)D concentration <50 nmol/L (HR 0·88; 95% CI 0·75, 1·02; p-interaction = 0·01) and increased risk in those with predicted 25(OH)D ≥ 50 nmol/L (HR 1·10; 95% CI 1·01, 1·20).

CONCLUSION

Monthly supplementation with high-dose vitamin D₃ was not of benefit for measures of depression overall, but there was some evidence of benefit in subgroup analyses.

CLINICAL TRIAL REGISTRATION

The trial is registered on the Australian New Zealand Clinical Trials Registry: ACTRN12613000743763. https://www.anzctr.org.au/.

The effect of vitamin D supplementation on risk of keratinocyte cancer - an exploratory analysis of the D-Health Randomised Controlled Trial

BACKGROUND

Vitamin D may play a role in prevention of keratinocyte cancer (KC), but observational studies examining the association between serum 25-hydroxy vitamin D concentration and KC are largely uninformative because sun exposure causes both KC and vitamin D production. There is scant evidence from clinical trials of supplementary vitamin D.

OBJECTIVES

To examine the effect of vitamin D supplementation on the risk of developing KC.

METHODS

We used data from the D-Health Trial, a randomised placebo-controlled trial of vitamin D supplementation (60,000 IU monthly for 5 years) among Australians aged ≥60 years. KC outcomes were captured through linkage to a national administrative dataset for those who consented (N=20,334; 95%). We used negative binomial regression to analyse the incidence of KC excisions and the incidence of actinic lesions treated using cryotherapy or serial curettage, and flexible parametric survival models for analysis of time to first KC excision.

RESULTS

Randomisation to vitamin D supplementation did not reduce the incidence of KC lesions treated by excision [incidence rate ratio (IRR) 1.04; 95% CI 0.98 - 1.11], the incidence of actinic lesions treated using other methods (IRR 1.01; 95% CI 0.95 - 1.08), or time to first histologically confirmed KC excision (hazard ratio 1.02; 95% CI 0.97 - 1.08). However, in subgroup analysis vitamin D increased the incidence of KC excisions in adults aged ≥70 years (IRR 1.13; 95% CI 1.04-1.23. p-value for interaction 0.01).

CONCLUSION

Vitamin D supplementation did not reduce the incidence of KC or other actinic lesions.

Vitamin D supplementation and antibiotic use in older Australian adults - an analysis of data from the D-Health Trial

BACKGROUND

Vitamin D supplementation may reduce the risk or severity of infection, but this has been investigated in few large population-based trials. We analyzed data from the D-Health Trial, using prescription of antibiotics as a surrogate for infection.

METHODS

The D-Health Trial is a randomized, double-blind, placebo-controlled trial in which 21,315 Australians aged 60-84 years were randomized to 60,000 IU of supplementary vitamin D3 or placebo monthly for 5 years. For this analysis, the primary outcome was the number of antibiotic prescription episodes; secondary outcomes were total number of prescriptions; repeat prescription episodes; and antibiotics for urinary tract infection. We estimated incidence rate ratios (IRRs) using negative binomial regression, and odds ratios using logistic regression.

RESULTS

Vitamin D supplementation slightly reduced the number of prescription episodes (IRR 0.98, 95% CI 0.95-1.01), total prescriptions (IRR 0.97, 95% CI 0.93-1.00), and repeat prescription episodes (IRR 0.96, 95% CI 0.93-1.00). There was stronger evidence of benefit in people predicted to have insufficient vitamin D at baseline (prescription episodes IRR 0.93, 95% CI 0.87-0.99).

CONCLUSIONS

Vitamin D may reduce the number of antibiotic prescriptions, particularly in people with low vitamin D status. This supports the hypothesis that vitamin D has a clinically relevant effect on the immune system.

Dietary practices after primary treatment for ovarian cancer: A qualitative analysis from the OPAL Study

BACKGROUND

Little is known about dietary practices of women who have completed primary treatment for ovarian cancer, many of whom will go on to experience cancer recurrence and have further treatment. Knowledge of dietary practices is needed to optimize care.

OBJECTIVE

To identify dietary practices after primary treatment for ovarian cancer and evaluate how these practices differ by disease recurrence and treatment status.

DESIGN

Women with invasive epithelial ovarian cancer were provided with an open-ended question after completing a food frequency questionnaire (FFQ): "Is there anything we haven't asked you about your diet in the last 1-2 months that you feel is important?"

PARTICIPANTS/SETTING

Participants in the Ovarian cancer Prognosis And Lifestyle (OPAL) Study in Australia.

MAIN OUTCOMES

Dietary practices after primary treatment for ovarian cancer and factors affecting these practices.

ANALYSIS

Participants' responses were analyzed using content analysis. Individual content codes were categorized and reported by recurrence and treatment status at questionnaire completion.

RESULTS

286 women provided responses on 363 questionnaires. Those undergoing further treatment for recurrence commonly reported dietary regimens with clinical indications (e.g., low fiber to avoid bowel obstructions, high energy/protein to minimize nutritional deficits). Those not undergoing further treatment frequently reported 'popular' diets (e.g., organic, plant-based, alkaline). For women with cancer recurrence, dietary practices were affected by poor appetite and treatment late effects. For women without recurrence, other comorbidities, geographical location, family and friends appeared to influence dietary practices. In both groups, nutrition information sources and personal beliefs informed dietary practices. Participant responses that referenced media or online sources often included misinformation.

CONCLUSIONS

Following primary treatment for ovarian cancer, women report dietary practices that may not be captured in standard FFQs. Dietary practices and factors affecting these practices likely differ by treatment and recurrence status. Improved access to evidence-based dietary information and support is needed.

The D-Health Trial: a randomised controlled trial of the effect of vitamin D on mortality

BACKGROUND

The effect of supplementing unscreened adults with vitamin D₃ on mortality is unclear. We aimed to determine whether monthly doses of vitamin D₃ influenced mortality in older Australians.

METHODS

We did a randomised, double-blind, placebo-controlled trial of oral vitamin D₃ supplementation (60 000 IU per month) in Australians 60 years or older who were recruited across the country via the Commonwealth electoral roll. Participants were randomly assigned (1:1), using automated computer-generated permuted block randomisation, to receive one oral gel capsule of either 60 000 IU vitamin D₃ or placebo once a month for 5 years. Participants, staff, and investigators were blinded to study group allocation. The primary endpoint was all-cause mortality assessed in all participants who were randomly assigned. We also analysed mortality from cancer, cardiovascular disease, and other causes. Hazard ratios (HRs) and 95% CIs were generated using flexible parametric survival models. This trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000743763.

FINDINGS

Between Feb 14, 2014, and June 17, 2015, we randomly assigned 21 315 participants, including 10 662 to the vitamin D group and 10 653 to the placebo group. In 4441 blood samples collected from randomly sampled participants (N=3943) during follow-up, mean serum 25-hydroxy-vitamin D concentrations were 77 (SD 25) in the placebo group and 115 (SD 30) nmol/L in the vitamin D group. Following 5 years of intervention (median follow-up 5·7 years [IQR 5·4-6·7]), 1100 deaths were recorded (placebo 538 [5·1%]; vitamin D 562 [5·3%]). 10 661 participants in the vitamin D group and 10 649 participants in the placebo group were included in the primary analysis. Five participants (one in the vitamin D group and four in the placebo group) were not included as they requested to be withdrawn and their data to be destroyed. The HR of vitamin D₃ effect on all-cause mortality was 1.04 [95% CI 0·93 to 1·18]; p=0·47)and the HR of vitamin D₃ effect on cardiovascular disease mortality was 0·96 (95% CI 0·72 to 1·28; p=0·77). The HR for cancer mortality was 1·15 (95% CI 0·96 to 1·39; p=0·13) and for mortality from other causes it was 0·83 (95% CI 0·65 to 1·07; p=0·15). The odds ratio for the per-protocol analysis was OR 1·18 (95% CI 1·00 to 1·40; p=0·06). In exploratory analyses excluding the first 2 years of follow-up, those randomly assigned to receive vitamin D had a numerically higher hazard of cancer mortality than those in the placebo group (HR 1·24 [95% CI 1·01-1·54]; p=0·05).

INTERPRETATION

Administering vitamin D₃ monthly to unscreened older people did not reduce all-cause mortality. Point estimates and exploratory analyses excluding the early follow-up period were consistent with an increased risk of death from cancer. Pending further evidence, the precautionary principle would suggest that this dosing regimen might not be appropriate in people who are vitamin D-replete.

FUNDING

The D-Health Trial is funded by National Health and Medical Research Council.

Dark Green Leafy Vegetable Intake, MTHFR Genotype, and Risk of Cutaneous Squamous Cell Carcinoma

BACKGROUND

Evidence suggests that consumption of dark green leafy vegetables may influence the decrease in the risk of cutaneous squamous cell carcinoma (SCC). Dark green leafy vegetables contain folate as a main component among other nutrients; thus, we hypothesised that their possible observed protective effect on SCC, observed in previous studies, would be more evident in persons with specific genotypes related to folate metabolism.

METHODS

Genotyping of methylenetetrahydrofolate reductase (MTHFR) gene variants rs1801133 (C677T) and rs1801131 (A1298C) was carried out for 1,128 participants in an Australian community-based longitudinal study of skin cancer. Dietary intakes were assessed through repeated Food Frequency Questionnaires (1992-1996), and all incident skin cancers were recorded in 1992-2007 and histologically confirmed. We assessed associations between intake of dark green leafy vegetables and SCC development in strata defined by genotype, by calculating relative risks (RRs) with 95% confidence intervals (CIs) using generalised linear models with negative binomial distribution and person-years of follow-up as offset.

RESULTS

High versus low intake of dark green leafy vegetables was associated with a lower risk of SCC tumours in carriers of the C677T variant allele (RR = 0.42, 95% CI = 0.23-0.75), and within wild-type A1298C homozygotes (RR = 0.43, 95% CI = 0.22-0.85).

CONCLUSION

The protective effect of dark green leafy vegetables on cutaneous SCC may be genotype-dependent. Folate metabolism-related gene polymorphisms should be considered when assessing the relation of green leafy vegetables to cancer risk.

Vitamin D supplementation and risk of falling: outcomes from the randomized, placebo-controlled D-Health Trial

BACKGROUND

Falls cause considerable morbidity and mortality in older people. It is unclear how vitamin D supplementation affects falls risk, particularly when taken at high doses. We sought to determine whether monthly high-dose vitamin D supplementation reduces risk and incidence of falls.

METHODS

We used data from the randomized, double-blind, placebo-controlled D-Health Trial conducted in Australia. Between February 2014 and May 2015, 21 315 participants aged 60-84 years were randomized (1:1) to monthly doses of either 60 000 IU of colecalciferol or placebo for a maximum of 5 years. People who reported a history of osteomalacia, sarcoidosis, hyperparathyroidism, hypercalcaemia or kidney stones or who were taking >500 IU/day supplementary vitamin D were ineligible. Each year, we collected blood samples from ~450 randomly sampled participants from each trial arm and measured 25-hydroxyvitamin D [25(OH)D]. Falls, a prespecified tertiary outcome, were ascertained using annual surveys and, for a subset of participants, 3-month falls diaries. The primary outcome for this analysis was any fall in the month before completing an annual survey. As part of our process to maintain blinding, we used random samples of participants (surveys, n = 16 000; diaries, n = 2400), with equal numbers per group. Participants with no outcome data were excluded. Following an intention-to-treat approach, we analysed outcomes using logistic, ordinal and negative binomial regression. Registration: Australian New Zealand Clinical Trials Registry (ACTRN12613000743763); registered 4 July 2013.

RESULTS

Mean treatment duration was 4.3 years (standard deviation [SD] = 1.4 years). Mean serum 25(OH)D concentrations during the trial were 114.8 (SD 30.3) nmol/L and 77.5 (SD 25.2) nmol/L in the vitamin D and placebo groups, respectively. Survey and diary analytic sets included 15 416 and 2200 participants, respectively; approximately half were randomized to vitamin D (surveys: 50.1%; diaries: 50.4%). Vitamin D had no effect on falling in the past month (odds ratio [OR] 1.02, 95% confidence interval [CI] 0.95-1.10). There was an interaction with body mass index (BMI) (P-interaction = 0.001); vitamin D increased risk in participants with BMI < 25 kg/m² (OR 1.25, 95% CI 1.09-1.43), but there was no effect in those with BMI ≥ 25 kg/m² (OR 0.95, 95% CI 0.87-1.04). Analyses of diary data were consistent with these findings. The incidence of hypercalcaemia and kidney stones did not differ between groups.

CONCLUSIONS

Monthly high-dose vitamin D supplementation did not reduce risk of falling. A possible increased risk of falling with vitamin D supplementation in people with normal BMI warrants further investigation.

Validation of a Short Dietary Questionnaire to Evaluate Dietary Intake in School-Aged Children 9–11 Years in Ho Chi Minh City, Vietnam

Objectives

Regular and timely assessment of children's diet is crucial in the context of increased childhood overweight and obesity in countries undergoing the nutrition transition. Presently, there is no quick, simple, validated dietary assessment tool to evaluate children's diet in Vietnam. Thus, this study will examine the reliability and validity of a newly developed short dietary questionnaire (SDQ) among school-aged children 9–11 years old in Ho Chi Minh City to assess whether they meet the Vietnamese dietary guidelines.

Methods

A validation study is being conducted among fifth-grade students (9–11 years old) from four primary schools representative for four areas of Ho Chi Minh, Vietnam. 29-item questions including intakes in food groups (6 core food groups, and 5 non-core food groups) and five mealtime behaviors over the last week will be validated against 24-hour recalls on 3 days during one week (2 weekdays and one weekend). The SDQ will be administrated two times within one-week interval to examine its reliability. The difference between the frequency of food groups intakes and mealtime behaviors from the SDQ and 3-day 24 hour recalls will be examined using paired t-test. Bland-Altman analysis with 95% limit of agreement will be used to examine level agreement between two methods. Weighted Kappa will be applied to identify misclassification between quintiles of frequency of consumption in food groups per week. Strength of agreement will be defined by the Landis and Koch value. Also, the Children Dietary Score reflecting adherence to the Vietnamese dietary guidelines will be developed to examine agreement between scores from SDQ and from the 24 hour recalls. These Children Dietary scores will be used to test the validity and reliability of the tool using the above tests. The Wilcoxon rank-sum test will be used to examine whether an increase in the number of serves/cups from the SDQ correlates with increases in grams of fruits/vegetables or water volume consumed.

Results

N/A.

Conclusions

The SDQ is expected to be used as a screening tool to assess whether school-aged children meet the Vietnamese dietary guidelines. This could support governments to help improve children's diet in a timely fashion.

Funding Sources

PhD scholarship from QUT and the Commonwealth Government of Australia.

Cancer survivors' perspectives of dietary information provision after cancer treatment: A scoping review of the Australian context

ISSUE ADDRESSED

To support survivor-centred care in Australia, this review maps current knowledge regarding adult cancer survivors' perspectives of dietary information provision post-treatment.

METHODS

A scoping review of research conducted in Australia within the past decade reported using PRISMA-ScR guidelines. Seven databases were searched (01/01/2009-05/06/2020) and records were independently screened by two researchers using eligibility criteria. Papers in the peer-reviewed literature with dietary information post-treatment as a primary and secondary outcome were eligible for inclusion. Data charting included participant characteristics, study methodology and cancer survivors' reports of dietary information provision post-treatment.

RESULTS

Of 531 records identified, 12 met eligibility criteria. Most studies included breast (58%) and colorectal (42%) cancer survivors within 5 years post-diagnosis (84%). Three studies were conducted amongst specific ethnic groups (Indigenous Australians, Chinese-Australians, Greek-Australians). Participants in the included studies commonly reported limited or ineffective dietary information from healthcare providers post-treatment. Cancer survivors identified a need for individualised information regarding dietary strategies to manage ongoing symptoms, professional support for weight management, and practical skills for healthy eating. Amongst ethnic groups, there was a need for dietary information that considers traditional foods and cultural beliefs, and is available in their native language. Cancer survivors valued ongoing dietary follow-up and support post-treatment, and suggested a variety of face-to-face and online delivery modes. Those residing in rural and remote areas reported barriers to accessing dietary information post-treatment including time, cost, and availability of local services.

CONCLUSIONS

There is scope to improve dietary information provision after cancer treatment in Australia. SO WHAT?: Dietary guidance post-treatment should consider individual needs, cultural background, and opportunity for ongoing follow-up and support.

Dietitian encounters after treatment for ovarian cancer

BACKGROUND

After ovarian cancer treatment, women report health issues that may be amenable to change with dietary support. The present study investigated how many women encounter a dietitian post-treatment and the factors associated with dietitian service use.

METHODS

We used data from a cohort of women with invasive epithelial ovarian cancer to identify socio-economic, clinical and personal factors associated with dietitian encounter after treatment completion. Data were collected at regular intervals using validated questionnaires up to 4 years post-treatment completion. Logistic regression (LR) and generalised linear mixed models (GLMM) were used to calculate adjusted odds ratios (OR) and 95% confidence intervals (CI) to assess factors associated with dietitian encounter at any time-point post-treatment (LR), as well as in the 3 months prior to a follow-up questionnaire (GLMM) to assess time-varying factors.

RESULTS

Of 819 women, 97 (12%) reported seeing a dietitian post-treatment. Factors associated with dietitian encounter were being overweight (OR_LR  = 1.7, CI = 1.1-2.8), having poorer self-rated health (OR_LR  = 2.5, CI = 1.2-5.2; OR_GLMM  = 2.3, CI = 1.2-4.4) or poorer diet quality (OR_LR  = 0.5, CI = 0.2-1.0) pre-diagnosis, treatment within the public health system (OR_GLMM  = 1.8, CI = 1.2-2.7), previous support from dietetic (OR_LR  = 3.1, CI = 1.8-5.4; OR_GLMM  = 2.8, CI = 1.8-4.2) or other allied health services (OR_LR  = 2.0, CI = 1.2-3.2; OR_GLMM  = 3.7, CI = 2.4-5.5), and having progressive disease at follow-up (OR_GLMM  = 2.2, CI = 1.4-3.3). Most women (86%) with ≥ 3 moderate-to-severe nutrition impact symptoms did not report a dietitian encounter post-treatment.

CONCLUSIONS

Few women encounter a dietitian post-treatment for ovarian cancer, including those with multiple nutrition impact symptoms. Further work is needed to engage those likely to benefit from dietitian support but less likely to seek or receive it.

Predicting deseasonalised serum 25 hydroxy vitamin D concentrations in the D-Health Trial: An analysis using boosted regression trees

BACKGROUND

The D-Health Trial aims to determine whether monthly high-dose vitamin D supplementation can reduce the mortality rate and prevent cancer. We did not have adequate statistical power for subgroup analyses, so could not justify the high cost of collecting blood samples at baseline. To enable future exploratory analyses stratified by baseline vitamin D status, we developed models to predict baseline serum 25 hydroxy vitamin D [25(OH)D] concentration.

METHODS

We used data and serum 25(OH)D concentrations from participants who gave a blood sample during the trial for compliance monitoring and were randomised to placebo. Data were partitioned into training (80%) and validation (20%) datasets. Deseasonalised serum 25(OH)D concentrations were dichotomised using cut-points of 50, 60 and 75 nmol/L. We fitted boosted regression tree models, based on 13 predictors, and evaluated model performance using the validation data.

RESULTS

The training and validation datasets had 1788 (10.5% <50 nmol/L, 23.1% <60 nmol, 48.8 <75 nmol/L) and 447 (11.9% <50 nmol/L, 25.7% <60 nmol/L, and 49.2% <75 nmol/L) samples, respectively. Ambient UV radiation and total intake of vitamin D were the strongest predictors of 'low' serum 25(OH)D concentration. The area under the receiver operating characteristic curves were 0.71, 0.70, and 0.66 for cut-points of <50, <60 and <75 nmol/L respectively.

CONCLUSIONS

We exploited compliance monitoring data to develop models to predict serum 25(OH)D concentration for D-Health participants at baseline. This approach may prove useful in other trial settings where there is an obstacle to exhaustive data collection.

The effect of vitamin D supplementation on acute respiratory tract infection in older Australian adults: an analysis of data from the D-Health Trial

BACKGROUND

Observational studies have linked vitamin D deficiency with acute respiratory tract infection, but results from randomised controlled trials are heterogeneous. We analysed data from the D-Health Trial to determine whether supplementing older Australian adults, recruited from the general population, with monthly doses of vitamin D reduced the risk, duration, and severity of acute respiratory tract infections.

METHODS

We used data from the D-Health Trial, a randomised, double-blind, placebo-controlled trial of monthly vitamin D supplementation, for which acute respiratory infection was a pre-specified trial outcome. Participants were supplemented and followed for up to 5 years. The trial was set within the Australian general population, using the Commonwealth Electoral Roll as the sampling frame, but also allowing some volunteers to participate. Participants were men and women aged 60 to 79 years (with volunteers up to age 84 years). Participants were randomly assigned to receive either vitamin D or placebo (1:1) using computer-generated permuted block randomisation, which was stratified by age, sex, and state. This was an automated process and the assignment list was not visible to study staff or investigators. Active and placebo gel capsules, identical in appearance to ensure masking, were labelled A and B and the code was not available to study staff or investigators. Participants were asked to report occurrence of acute respiratory symptoms over the previous month via annual surveys, and a subset of participants completed 8-week respiratory symptom diaries in winter. As part of our process to maintain blinding, a random sample of participants was selected for analysis of survey data and a separate sample selected for analysis of diary data. Blood samples were obtained from a random sample of participants (about 450 per group per year) and serum 25-hydroxy vitamin D (25[OH]D) concentrations were measured to monitor adherence. We used regression models to estimate odds ratios (OR), rate ratios, and rate differences. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000743763.

FINDINGS

Between Jan 13, 2014, and May 26, 2015, 421 207 invitations were sent, 40 824 people were interested in participating, and 21 315 participants were recruited and randomised. Of the 16 000 participants selected for potential analysis of survey data, 15 373 were included in the analysis; 295 in the vitamin D group and 332 in the placebo group who were missing data for all five annual surveys were excluded from the analysis. Of the 3800 selected for potential analysis of diary data, 3070 were invited to complete the diaries because 730 had already withdrawn. 2598 people were included in the analysis; 218 people in the vitamin D group and 254 in the placebo group were missing data and were therefore excluded from the analysis. In blood samples collected from randomly sampled participants throughout the trial, the mean serum 25(OH)D concentration was 114·8 (SD 30·3) nmol/L in the vitamin D group and 77·5 (25·2) nmol/L in the placebo group. Vitamin D supplementation did not reduce the risk of acute respiratory tract infection (survey OR 0·98, 95% CI 0·93 to 1·02; diary OR 0·98, 0·83 to 1·15). Analyses of diary data showed reductions in the overall duration of symptoms and of severe symptoms, but these were small and unlikely to be clinically significant.

INTERPRETATION

Monthly bolus doses of 60 000 IU of vitamin D did not reduce the overall risk of acute respiratory tract infection, but could slightly reduce the duration of symptoms in the general population. These findings suggest that routine vitamin D supplementation of a population that is largely vitamin D replete is unlikely to have a clinically relevant effect on acute respiratory tract infection.

FUNDING

National Health and Medical Research Council.

Needs, preferences, and experiences of adult cancer survivors in accessing dietary information post-treatment: A scoping review

INTRODUCTION

To support provision of healthy lifestyle information tailored to patients' needs and preferences, this review maps adult cancer survivors' self-reported needs, preferences, and experiences accessing dietary information post-treatment.

METHODS

A scoping review of research published within the past decade conducted using PRISMA-ScR guidelines. Seven databases were searched in June 2020.

RESULTS

Of 15,973 articles identified, 57 met eligibility criteria. Studies most frequently included survivors of breast cancer (49%), persons aged 40+ years (95%), ≤5 years post-diagnosis (54%), and residing in North America (44%). Cancer survivors commonly identified needing information regarding healthy eating, particularly practical skills, and support in changing dietary behaviours. Preferences included specific recommendations, direct communication with healthcare professionals, and peer support from other cancer survivors. In practice, survivors frequently reported receiving generic advice from healthcare professionals, limited dietary follow-up, and lack of referral to support. Unmet needs in healthcare settings led to dietary information-seeking elsewhere; however, survivors indicated difficulty identifying credible sources. Personal beliefs and desire for involvement in care motivated dietary information-seeking post-treatment.

CONCLUSION

Cancer survivors' experiences accessing dietary information post-treatment do not align with needs and preferences. Less is known about survivors who are young adults, >5 years post-diagnosis, and living in rural areas.

Risk of Melanoma Recurrence After Diagnosis of a High-Risk Primary Tumor

Importance

With emerging new systemic treatments for metastatic melanoma, early detection of disease recurrence is increasingly important.

Objective

To investigate the risk of melanoma recurrence in patients with a localized melanoma at a high risk of metastasis.

Design, Setting, and Participants

A total of 1254 patients with newly diagnosed, histologically confirmed tumor category T1b to T4b melanoma in Queensland, Australia, were recruited prospectively between October 1, 2010, and October 1, 2014, for participation in a cohort study. Data analysis was conducted from February 8, 2018, to February 20, 2019. We used Cox proportional hazards regression analysis to examine associations between patient and tumor factors and melanoma recurrence.

Exposures

Disease-free survival (DFS) by melanoma tumor category defined by the 7th vs 8th editions of the AJCC Cancer Staging Manual (AJCC 7 vs AJCC 8).

Main Outcomes and Measures

Melanoma recurrences were self-reported through follow-up questionnaires administered every 6 months and confirmed by histologic or imaging findings.

Results

Of 1254 patients recruited, 825 individuals (65.8%) agreed to participate. Thirty-six were found to be ineligible after providing consent and a further 89 patients were excluded after reclassifying tumors using AJCC 8, leaving 700 participants with high-risk primary melanoma (mean [SD] age, 62.2 [13.5] years; 410 [58.6%] men). Independent predictors of recurrence were head or neck site of primary tumor, ulceration, thickness, and mitotic rate greater than 3/mm2 (hazard ratio, 2.36; 95% CI, 1.19-4.71). Ninety-four patients (13.4%) developed a recurrence within 2 years of diagnosis: 66 tumors (70.2%) were locoregional, and 28 tumors (29.8%) developed at distant sites. After surgery for locoregional disease, 37 of 64 patients (57.8%) remained disease free at 2 years, 7 patients (10.9%) developed new locoregional recurrence, and 20 patients (31.3%), developed distant disease. Two-year DFS was similar when comparing AJCC 7 and AJCC 8, for T1b (AJCC 7, 253 [93.3% DFS]; AJCC 8, 242 [93.0% DFS]) and T4b (AJCC 7 and AJCC 8, 50 [68.0% DFS] category tumors in both editions. Patients with T2a to T4a tumors who did not have a sentinel lymph node biopsy (SLNB) at diagnosis had lower DFS than patients with the same tumor category and a negative SLNB (T2a: 136 [91.1%; 95% CI, 86.4-95.9] vs 96 [96.9%; 95 % CI, 93.4-100.0]; T4a: 33 [78.8%; 95% CI, 64.8-92.7] vs 6 [83.3; 95% CI, 53.5-100.0]).

Conclusions and Relevance

These findings suggest that 13.4% of patients with a high-risk primary melanoma will experience disease recurrence within 2 years. Head or neck location of initial tumor, SLNB positivity, and signs of rapid tumor growth may be associated with primary melanoma recurrence.

Retrospective self-reported dietary supplement use by Australian military personnel during deployment to Iraq and Afghanistan: results from the Middle East Area of Operations Health Study

The use of dietary supplements is popular among military personnel. However, there is a lack of understanding about the changes in use during deployment and the specific factors associated with such changes. This study retrospectively examined changes in the pattern of supplement use among Australian veterans during their deployment to Iraq (n = 8848) and Afghanistan (n = 6507) between 2001 and 2009 and identified work-related circumstances that were associated with these changes. The frequency of use of supplements at present and during deployment was assessed. Multiple logistic regression analysis was used to compare the use of supplements among different groups and among those with different deployment experiences. The study found that overall use of supplements was highest on deployment to Afghanistan (27.8%) compared with deployment to Iraq (22.0%, p < 0.001) or after deployment (current use, 21.2%; p < 0.001). Personnel who were younger or who were at the rank of noncommissioned officer were more likely to use dietary supplements. Men were more likely to use body-building supplements, whereas women more often used weight-loss supplements. Those veterans who did not report using supplements regularly on deployment were far less likely to use them subsequently. Combat exposure, mixed duty cycles, and working long hours during deployment were associated with higher supplement use. The findings confirmed that supplement use in the military reflects the unique demands and stressors of defence service.

Associations between Community Environmental-Level Factors and Diet Quality in Geographically Isolated Australian Communities

Remote Indigenous Australians experience disproportionately poor cardio-metabolic health, which is largely underpinned by adverse dietary intake related to social determinants. Little evidence exists about the community environmental-level factors that shape diet quality in this geographically isolated population group. This study aimed to explore the modifiable environmental-level factors associated with the features of dietary intake that underpin cardio-metabolic disease risk in this population group. Community-level dietary intake data were estimated from weekly store sales data collected throughout 2012 and linked with concurrent social, built, and physical environmental dimension data for 13 remote Indigenous Australian communities in the Northern Territory. Statistical analyses were performed to investigate associations. At the community level, store sales of discretionary foods were lower in communities with greater distance to a neighbouring store (r = −0.45 (p < 0.05)). Sales of sugar-sweetened beverages were lower in communities with higher levels of household crowding (r = −0.55 (p < 0.05)), higher levels of Indigenous unemployment (r = −0.62 (p = 0.02)), and greater distance to neighbouring stores (r = −0.61 (p = 0.004)). Modifiable environmental-level factors may be associated with adverse diet quality in remote Indigenous Australian communities and further investigations of these factors should be considered when developing policies to improve dietary intake quality in geographically isolated populations.

Regular Sunscreen Use and Risk of Mortality: Long-Term Follow-up of a Skin Cancer Prevention Trial

INTRODUCTION

Sunscreen is widely used to protect the skin from harmful effects of sun exposure. However, there are concerns that sunscreens may negatively affect overall health. Evidence of the general safety of long-term regular sunscreen use is therefore needed.

METHODS

The effect of long-term sunscreen use on mortality was assessed over a 21-year period (1993-2014) among 1,621 Australian adults who had participated in a randomized skin cancer prevention trial of regular versus discretionary sunscreen use (1992-1996). In 2018, an intention-to-treat analysis was conducted using Cox proportional hazards regression to compare death rates in people who were randomized to apply sunscreen daily for 4.5years, versus randomized to use sunscreen at their usual, discretionary level. All-cause mortality and deaths resulting from cardiovascular disease, cancer, and other causes were considered.

RESULTS

In total, 160 deaths occurred in the daily sunscreen group compared with 170 deaths in the discretionary sunscreen group (hazard ratio=0.94, 95% CI=0.76, 1.17); 59vs 76 cardiovascular disease deaths (hazard ratio=0.77, 95% CI=0.55, 1.08), 63vs 58 cancer deaths (hazard ratio=1.09, 95% CI=0.76, 1.57), and 45vs 44 deaths resulting from other causes (hazard ratio=1.02, 95% CI=0.67, 1.54) occurred respectively.

CONCLUSIONS

Regular use of a sun protection factor 16 sunscreen on head, neck, arms, and hands for 4.5years did not increase mortality.

A randomized placebo-controlled trial of vitamin D supplementation for reduction of mortality and cancer: Statistical analysis plan for the D-Health Trial

Background

Many observational studies have reported an association between vitamin D and non-skeletal health outcomes. The D-Health Trial was launched to determine if supplementing the older population with high monthly doses of Vitamin D can prevent cancer and premature mortality. The intervention is ongoing but here we provide a detailed statistical analysis plan for the primary and secondary outcomes of the D-Health Trial.

Methods/design

The D-Health Trial is a double-blind, randomized, placebo-controlled trial. Between February 2014 and May 2015, 21,315 people were randomized in a 1:1 ratio to receive monthly doses of either 60,000 IU of cholecalciferol (vitamin D₃) or placebo for five years. The primary outcome is all-cause mortality and the secondary outcomes are total cancer incidence and colorectal cancer incidence. These will be ascertained via linkage to death and cancer registries. The primary analysis for each outcome will follow an intention-to-treat approach; we will use flexible parametric survival models to investigate the association between supplementation and time to an event. We describe in detail sophisticated secondary analyses that consider non-compliance and contamination due to off-study supplementation.

Conclusions

Publication of this statistical analysis plan in advance of the intervention's completion, and adherence to it, will avoid data-driven analyses of the primary and secondary outcomes and ensure robust reporting of outcomes.

Clinical trial registration number

Australian New Zealand Clinical Trials Registry: ACTRN12613000743763. Registered on 4 July 2013.

Associations of Statins and Diabetes with Diagnosis of Ulcerated Cutaneous Melanoma

Ulcerated primary melanomas are associated with an inflammatory tumor microenvironment. We hypothesized that systemic proinflammatory states and anti-inflammatory medications are also associated with a diagnosis of ulcerated melanoma. In a cross-sectional study of 787 patients with newly diagnosed clinical stage IB or II melanoma, we estimated odds ratios for the association of proinflammatory factors (high body mass index, diabetes, cardiovascular disease, hypertension, and smoking) or the use of anti-inflammatory medications (statins, aspirin, corticosteroids, and nonsteroidal anti-inflammatory drugs), with ulcerated primary melanoma using regression models and subgroup analyses to control for melanoma thickness and mitotic rate. On the basis of information from 194 patients with ulcerated and 593 patients with nonulcerated primary melanomas, regular statin users had lower likelihood of a diagnosis of ulcerated primary melanoma (odds ratio 0.67, 95% confidence interval 0.45-0.99), and this association remained after adjusting for age, sex, thickness, and mitosis. When analysis was limited to melanomas that were ≤2 mm thick and had ≤2 mitoses/mm2 (40 ulcerated; 289 without ulceration), patients with diabetes had significantly raised odds of diagnosis of ulcerated melanoma (odds ratio 2.90, 95% confidence interval 1.07-7.90), adjusted for age, sex, body mass index, and statin use. These findings support our hypotheses that statin use is inversely associated, and diabetes is positively associated, with ulcerated melanoma.

Dietary behaviours, weight loss attempts and change in waist circumference: 15-year longitudinal study in Australian adults

BACKGROUND AND OBJECTIVES

Dietary behaviours are suitable as clearly identifiable targets of dietary counselling to prevent weight gain. We therefore investigated associations between dietary behaviours, weight loss attempts and waist circumference change.

METHODS AND STUDY DESIGN

Participants were a community-based sample population residing in Nambour, Australia, including 1,317 adults, aged 25-75 years at baseline. Waist circumference was measured in 1992 and 2007, and dietary behaviours data were derived concurrently from repeated self-completed short dietary questions. Multivariable models, stratified by sex, were adjusted for potential confounders.

RESULTS

In men, consumption of visible fat on meat and in women, weight loss attempts in the last 10 years were the most important predictors of waist circumference gain independent of socio-demographic and lifestyle characteristics and energy intake. Men who consumed most visible fat on meat had a 2.6 times larger yearly increase in waist circumference than men who tended to cut the fat off meat: 0.47 (95% CI 0.23, 0.72) vs 0.18 (95% CI 0.01, 0.34) cm/year, p=0.01. Women who reported that they were always trying to lose weight had a 2.7 times larger yearly increase in waist circumference than women who never tried to lose weight: 0.78 (0.54, 1.02) vs 0.29 (0.06, 0.52) cm/year, p=0.0001. Other dietary behaviours were not associated with change in waist circumference.

CONCLUSIONS

Consumption of visible fat on meat by men and more frequent attempts to lose weight by women were main dietary behaviours associated with gain in abdominal adiposity in Australian adults.

Vitamin D intake in Australian adults and the modeled effects of milk and breakfast cereal fortification

OBJECTIVE

Vitamin D intake from foods or supplements is a safe and attractive means to improve vitamin D status of populations. The aim of this study was to help identify population subgroups that would benefit most from efforts to increase intake. To do so, we investigated which personal characteristics are associated with vitamin D intake in an Australian population and modeled possible effects of expanded food fortification practices.

METHODS

We investigated vitamin D intake in a population-based random sample of 785 adults, using a validated food frequency questionnaire, and assessed associations with personal and behavioral characteristics. We identified vitamin D food sources and modeled the hypothetical effects of blanket fortification of milk and breakfast cereals.

RESULTS

Average total vitamin D intake was 4.4 (±4.0) μg/g and below adequate intake for most participants in all age and sex subgroups. Higher intake was associated with being female, having a serious medical condition, energy intake below the median, and vitamin D supplement use (all P < 0.05). The "meat, fish, and eggs" food group contributed most to total vitamin D intake (51%), followed by dairy products and related foods (43%). If all milk and breakfast cereals were to be fortified with vitamin D, the average intake of vitamin D from foods would increase from 3.6 (±2.4) μg/d to 6.3 (±3.2) μg/d, with similar increases in all age and sex subgroups.

CONCLUSIONS

Vitamin D intake in Australia is generally below recommended levels, and few personal characteristics help to identify subgroups with low intake. Blanket vitamin D fortification of milk and breakfast cereals would substantially increase average vitamin D intake in Australian adults of all ages.

Effect of vitamin D supplementation on antibiotic use: a randomized controlled trial

BACKGROUND

Observational data suggested that supplementation with vitamin D could reduce risk of infection, but trial data are inconsistent.

OBJECTIVE

We aimed to examine the effect of oral vitamin D supplementation on antibiotic use.

DESIGN

We conducted a post hoc analysis of data from pilot D-Health, which is a randomized trial carried out in a general community setting between October 2010 and February 2012. A total of 644 Australian residents aged 60-84 y were randomly assigned to receive monthly doses of a placebo (n = 214) or 30,000 (n = 215) or 60,000 (n = 215) IU oral cholecalciferol for ≤12 mo. Antibiotics prescribed during the intervention period were ascertained by linkage with pharmacy records through the national health insurance scheme (Medicare Australia).

RESULTS

People who were randomly assigned 60,000 IU cholecalciferol had nonsignificant 28% lower risk of having antibiotics prescribed at least once than did people in the placebo group (RR: 0.72; 95% CI: 0.48, 1.07). In analyses stratified by age, in subjects aged ≥70 y, there was a significant reduction in antibiotic use in the high-dose vitamin D compared with placebo groups (RR: 0.53; 95% CI: 0.32, 0.90), whereas there was no effect in participants aged <70 y (RR: 1.07; 95% CI: 0.58, 1.97) (P-interaction = 0.1).

CONCLUSION

Although this study was a post hoc analysis and statistically nonsignificant, this trial lends some support to the hypothesis that supplementation with 60,000 IU vitamin D/mo is associated with lower risk of infection, particularly in older adults. The trial was registered at the Australian New Zealand Clinical Trials Registry (anzctr.org.au) as ACTRN12609001063202.

Predicting vitamin D deficiency in older Australian adults

OBJECTIVE

There has been a dramatic increase in vitamin D testing in Australia in recent years, prompting calls for targeted testing. We sought to develop a model to identify people most at risk of vitamin D deficiency.

DESIGN AND PARTICIPANTS

This is a cross-sectional study of 644 60- to 84-year-old participants, 95% of whom were Caucasian, who took part in a pilot randomized controlled trial of vitamin D supplementation.

MEASUREMENTS

Baseline 25(OH)D was measured using the Diasorin Liaison platform. Vitamin D insufficiency and deficiency were defined using 50 and 25 nmol/l as cut-points, respectively. A questionnaire was used to obtain information on demographic characteristics and lifestyle factors. We used multivariate logistic regression to predict low vitamin D and calculated the net benefit of using the model compared with 'test-all' and 'test-none' strategies.

RESULTS

The mean serum 25(OH)D was 42 (SD 14) nmol/1. Seventy-five per cent of participants were vitamin D insufficient and 10% deficient. Serum 25(OH)D was positively correlated with time outdoors, physical activity, vitamin D intake and ambient UVR, and inversely correlated with age, BMI and poor self-reported health status. These predictors explained approximately 21% of the variance in serum 25(OH)D. The area under the ROC curve predicting vitamin D deficiency was 0·82. Net benefit for the prediction model was higher than that for the 'test-all' strategy at all probability thresholds and higher than the 'test-none' strategy for probabilities up to 60%.

CONCLUSION

Our model could predict vitamin D deficiency with reasonable accuracy, but it needs to be validated in other populations before being implemented.

Plasma omega-3 and omega-6 concentrations and risk of cutaneous basal and squamous cell carcinomas in Australian adults

Laboratory-based evidence suggests that omega-3 and omega-6 polyunsaturated fatty acids may affect skin photocarcinogenesis, but epidemiologic evidence is inconsistent. In 1,191 White Australian adults, we prospectively investigated associations between baseline plasma concentrations of omega-3 and omega-6 fatty acids and cutaneous basal cell carcinomas (BCC) and squamous cell carcinomas (SCC). Relative risks (RR) and 95% confidence intervals (CI) were estimated on the basis of number of histologically confirmed tumors diagnosed during follow-up (1997-2007). Plasma eicosapentaenoic acid (EPA) concentrations and omega-3/-6 ratio showed significant inverse associations with SCC tumors, comparing higher tertiles with the lowest, in age- and sex-adjusted models (Ptrend = 0.02 and 0.03, respectively) which weakened after adjustment for past sun exposure. Associations between EPA and SCC were stronger among participants with a history of skin cancer at baseline (n = 378; highest vs. lowest tertile: RR = 0.50; 95% CI, 0.28-0.92; Ptrend = 0.01). Total omega-6 was inversely associated with BCC tumors in multivariate models (P = 0.04; highest vs. lowest tertile: RR = 0.71; 95% CI, 0.51-0.99), and more strongly in the subgroup with past skin cancer. Linoleic and linolenic acids were also inversely associated with BCC occurrence in this subgroup. When fatty acids were analyzed as continuous variables, however, there was no evidence of any linear or nonlinear associations. This study provides some support for reduced skin cancer risk with high plasma concentrations of omega-3 and omega-6 fatty acids, but results depended on how fatty acid data were modeled. Further investigation of these associations in larger datasets is needed.

Recruitment and results of a pilot trial of vitamin D supplementation in the general population of Australia

CONTEXT

The benefits of high serum levels of 25-hydroxyvitamin D [25(OH)D] are unclear. Trials are needed to establish an appropriate evidence base.

OBJECTIVE

We plan to conduct a large-scale trial of vitamin D supplementation for the reduction of cancer incidence and overall mortality and report here the methods and results of a pilot trial established to inform its design.

DESIGN

Pilot D-Health was a randomized trial carried out in a general community setting with 12 months intervention and follow-up.

PARTICIPANTS

Participants were 60- to 84-yr-old residents of one of the four eastern Australian states who did not have any vitamin D-related disorders and who were not taking more than 400 IU supplementary vitamin D per day. A total of 644 participants were randomized, and 615 completed the study (two persons withdrew because of nonserious adverse events).

INTERVENTIONS

The interventions were monthly doses of placebo or 30,000 or 60,000 IU vitamin D(3).

MAIN OUTCOMES

The main outcomes were the recruitment rate and changes in serum 25(OH)D.

RESULTS

Ten percent of those approached were recruited. At baseline, the mean 25(OH)D was 42 nmol/liter in all three study arms. The mean change in 25(OH)D in the placebo group was 0.12 nmol/liter, compared with changes of 22 and 36 nmol/liter in the 30,000- and 60,000-IU groups, respectively.

CONCLUSIONS

The D-Health pilot has shown that a large trial is feasible in Australia and that a dose of 2000 IU/d will be needed to ensure that a large proportion of the population reaches the target serum 25(OH)D level.

Intake of omega-3 and omega-6 fatty acids and risk of basal and squamous cell carcinomas of the skin: a longitudinal community-based study in Australian adults

Intake of omega-3 and omega-6 fatty acids may modify the risk of basal and squamous cell carcinoma of the skin (BCC and SCC), but population-based evidence is limited and inconsistent. We examined prospectively associations between intake of omega-3 and omega-6 fatty acids estimated from food frequency questionnaires and BCC and SCC incidence among 1322 randomly selected adults in Nambour, Australia. Relative risks (RR) and 95% confidence intervals (CI) were estimated based on histologically confirmed tumors diagnosed between 1997 and 2007. Incidence of BCC was lowest in the middle third of both total omega-6 intake (RR(mv.adj) = 0.74, 95% CI = 0.56-0.97) and linoleic acid intake (RR(mv.adj) = 0.75, 95% CI = 0.57-0.99) compared with the lowest third of intake. Evidence for associations with SCC was weak, though persons with arachidonic acid intake in the middle third had a marginally increased risk of SCC (RR(mv.adj) = 1.42, 95% CI = 1.00-2.02). Consumption of omega-3 fatty acids was not associated with subsequent skin cancer risk. Suggestion that intake of arachidonic acid may be associated with increased SCC incidence and total omega-6 with reduced BCC from our study is still highly uncertain and may be due to chance. These data do not support an association between these fatty acids and risk of BCC or SCC.

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.

Longitudinal change in diet quality in Australian adults varies by demographic, socio-economic, and lifestyle characteristics

Knowledge of determinants of change in diet quality is needed, but it is relatively limited to date and mostly available from cross-sectional studies. We investigated longitudinal change in diet quality and its associations with period of birth (birth cohort) and socio-demographic and lifestyle characteristics. We used dietary intake data collected by FFQ in 1992, 1996, and 2007 from a population-based random sample of adults comprising 1511 men and women aged 25-75 y at baseline and applied generalized estimating equations to examine determinants of long-term change in diet quality, calculated using a diet quality index reflecting dietary guidelines for Australian adults. Information on socio-demographic and lifestyle factors was derived from self-reported questionnaires. Multivariable models, stratified by sex, were adjusted for confounders. We showed that there was an overall increase in diet quality in both men and women, but scores related to intake of fruit (men only), cereals, and food variety decreased during a 15-y follow-up. Younger age, higher occupational level (men only), and low to medium level of physical activity and hormone replacement therapy use in women were independently associated with greater improvement in diet quality over time (P < 0.05). In conclusion, despite an overall improvement in diet quality over time, this study suggests that efforts to further improve diet quality in Australia should focus on increasing consumption of fruit, cereals, and a greater variety of foods. More evidence from studies that assess change in dietary quality in longitudinal studies is needed to corroborate these findings.