Prevalence of interpersonal violence against women and men in New Zealand: results of a cross-sectional study

OBJECTIVE

To determine prevalence rates of non-partner and partner violence (IPV) in men and women from a population-based study.

METHODS

We recruited 2,887 randomly selected respondents (1,464 women and 1,423 men) from three regions of New Zealand between 2017 and 2019. Face-to-face interviews using a questionnaire adapted from the WHO multi-country study on violence against women was used for data collection.

RESULTS

Physical violence by non-partners was most commonly experienced by men (39.9% lifetime exposure) compared with 11.9% of women. More women (8.2%) experienced lifetime non-partner sexual violence compared with men (2.2%). About 29% of men and women reported at least one act of physical-IPV in their lifetime, and about 12.4% of women and 2.1% of men reported at least one act of lifetime sexual IPV. More women than men reported serious injuries, fear, and physical and mental health impacts following IPV experience.

CONCLUSIONS

These findings indicate high prevalence of interpersonal violence exposure in the population, with marked gender differences in the types and impacts of violence reported. Implications for public health: Study results call for the urgent implementation of violence prevention programs, and funding for both services to rehabilitate people who have perpetrated violence and services to support recovery of those affected.

Modifiable Early Childhood Risk Factors for Obesity at Age Four Years

Background: Childhood obesity is associated with an increased risk of adult obesity and related chronic disease. Our aim was to identify modifiable exposures that are independently associated with obesity in the preschool age group. Methods: A prospective cohort study of 5734 children in New Zealand with anthropometric measurements was completed at age 4.5 years. The modifiable exposures of interest, measured at age 9 months and 2 years, were: food security during infancy; and, at age 2 years, screen time; sleep duration; and takeaway food and soft drink intake. The risk of obesity independently associated with each exposure was determined using Binomial and Poisson regression and described using adjusted risk ratios (RRs) and 95% confidence intervals (CIs), after controlling for confounding variables including gender, ethnicity, birth weight, and mother's age. The probability of obesity given cumulative exposures to the four risk factors and the population attributable fraction (PAF) were estimated. Results: Lower food security during infancy (<mean study sample score; RR = 1.32; 95% CI : 1.06-1.64) and, at age 2 years, more screen time (>1 hour/day; RR = 1.22; 95% CI : 1.01-1.48), shorter sleep duration (≤11.5 hours/day; RR = 1.30; 95% CI : 1.05-1.61), and weekly to daily consumption of takeaway/soft drink (RR = 1.25, 95% CI : 1.00-1.57) were independently associated with an increased risk of obesity at age 4.5 years. The cumulative PAF for childhood obesity was 42.9%, under an ideal scenario where all risk factors were eliminated. Conclusion: Exposure to modifiable factors by age 2 years is associated with obesity at age 4.5 years. Interventions to prevent childhood obesity need to be effective during infancy.

Change in prevalence rates of physical and sexual intimate partner violence against women: data from two cross-sectional studies in New Zealand, 2003 and 2019

OBJECTIVES

To explore changes in reported prevalence of physical and sexual intimate partner violence (IPV) between 2003 and 2019. The impact of sociodemographic differences between the two samples and between group differences were also examined. Changes in attitudes supportive of violence and in help-seeking behaviour following disclosure were also explored.

DESIGN

Two cross-sectional studies.

SETTING AND PARTICIPANTS

Cross-sectional studies on family violence conducted in New Zealand in 2003 and 2019. Ever-partnered female respondents aged 18-64 years old were included (2003 n=2674, 2019 n=944).

MAIN OUTCOME MEASURES

Prevalence rates of lifetime and past 12-month physical and sexual IPV, attitudes towards gender roles and acceptability of a man hitting his wife, help sought and received following disclosure were compared between the study years.

RESULTS

Lifetime prevalence of physical IPV was unchanged between 2003 and 2019 (AOR=0.89; 95% CI 0.73 to 1.08). There was a significant decrease in the proportion of women who reported experiencing 12-month physical IPV (AOR=0.53; 95% CI 0.29 to 0.97). Small reductions in rates for lifetime sexual IPV were also observed (AOR=0.74; 95% CI 0.59 to 0.95). In 2019, fewer women agreed with one or more statements supportive of traditional gender roles (48.1% (95% CI 45.7% to 50.5%) in 2003; 38.4% (95% CI 33.8% to 43.2%) in 2019). A significant decrease was noted in the proportion of women who sought help from informal sources (from 71.3% (95% CI 68.1% to 74.2%) in 2003 to 64.6% (95% CI 58.7% to 70.1%) in 2019). No significant changes in seeking help from formal sources, or perceived helpfulness from any source were noted.

CONCLUSION

While the reductions in 12-month physical and lifetime sexual IPV are positive, prevention efforts need to be established, maintained and strengthened to address the substantial lifetime prevalence of IPV. Efforts to strengthen responses from formal and informal sources continue to be needed.

Change in prevalence of psychological and economic abuse, and controlling behaviours against women by an intimate partner in two cross-sectional studies in New Zealand, 2003 and 2019

OBJECTIVES

Changes in reported lifetime prevalence of psychological abuse, controlling behaviours and economic abuse between 2003 and 2019, and past 12-month prevalence of psychological abuse by an intimate partner were examined.

DESIGN

Cross-sectional analysis.

SETTING AND PARTICIPANTS

Data came from two surveys of family violence in New Zealand, conducted in 2003 and 2019. Respondents were ever partnered women aged 18-64 years old (2003 n=2673; 2019 n=935).

MAIN OUTCOME MEASURES

Prevalence rates for psychological abuse, controlling behaviours and economic abuse were compared between the two study years using logistic regression. Sociodemographic and economic correlates of each abuse subtype were investigated. Interactions were examined between sociodemographic factors and the study year for reported prevalence rates.

RESULTS

There was a reduction in reported past 12-month experience of two or more acts of psychological intimate partner violence (IPV) from 8.4% (95% CI 7.3 to 9.6) in 2003 to 4.7% (95% CI 3.2 to 6.2) in 2019. The reported lifetime prevalence of two or more acts of controlling behaviours increased from 8.2% in 2003 (95% CI 7.0 to 9.5) to 13.4% in 2019 (95% CI 11.0 to 15.7). Lifetime prevalence of economic IPV also increased from 4.5% in 2003 (95% CI 3.5 to 5.5) to 8.9% in 2019 (95% CI 6.7 to 11.1). Those who were divorced/separated or cohabiting, and those living in the most deprived areas were more likely to report past year psychological IPV, lifetime controlling behaviours and economic abuse. A higher proportion of women who were married or cohabiting reported controlling behaviours in 2019 compared with 2003.

CONCLUSION

While the reduction in reported past year psychological IPV is encouraging, the increase in the lifetime prevalence of controlling behaviours and economic abuse from 2003 to 2019 is worth critical evaluation. Results highlight potential gaps in current IPV prevention programmes, the need to identify and address underlying drivers of abusive behaviour and the importance of measuring multiple forms of IPV independently.

Risk factors for reporting adverse events and for study withdrawal in a population-based trial of vitamin D supplementation

With increasing numbers of randomized controlled trials (RCTs) investigating potential health events of vitamin D supplementation, a better understanding is required of the risk factors for adverse events and for study withdrawals. This analysis aimed to identify baseline risk factors of reporting an adverse event in a multi-year randomized double-blinded placebo-controlled trial of vitamin D supplementation. The secondary aim was to investigate if adverse events were associated with study withdrawals. We analyzed data from the Vitamin D Assessment (ViDA) study: 5110 adults, aged 50-84 years, living in Auckland, New Zealand. Monthly doses of 100,000 IU vitamin D3 or placebo were mailed to participants homes, with a questionnaire to collect data on adverse events and adherence to the study capsule (initially monthly, then 4-monthly). Median follow-up was 3.3 years. Data were analysed using multivariable log-binomial regression and Cox-regression. During the follow-up period, 818 people reported adverse events and 412 withdrew or stopped returning questionnaires. Vitamin D was not associated with reporting of adverse events. Of sociodemographic factors, ethnicity was associated with reporting adverse events: compared to European participants, Maori and Pacific Islander people were more likely to report an adverse event. Non-smokers were more likely to report an adverse event, compared to smokers (adjusted hazard ratio (HR) = 1.80; 95%CI = 1.24, 2.62); as were those who had reported a history of depression (adjusted HR = 1.27; 95%CI = 1.01, 1.60) or a recent cough or cold (adjusted HR = 1.22; 95%CI = 1.03, 1.44) at baseline. Reporting of adverse events was not associated with withdrawals (adjusted HR = 1.12; 95%CI = 0.86, 1.46). These data did not identify any clear pattern in the factors associated with self-reported adverse events, which themselves did not increase risk of withdrawals.

Monthly high-dose vitamin D supplementation does not increase kidney stone risk or serum calcium: results from a randomized controlled trial

BACKGROUND

A growing number of randomized controlled trials (RCTs) are investigating the potential health benefits of high-dose vitamin D supplementation. However, there are limited RCT data on the safety of calcium-related adverse effects.

OBJECTIVE

We investigated the incidence of kidney stone and hypercalcemia events in a large, population-based RCT of vitamin D supplementation.

DESIGN

The Vitamin D Assessment (ViDA) study was a randomized, double-blind, placebo-controlled trial of vitamin D supplementation in 5110 participants in Auckland, New Zealand. This trial investigated the impact of monthly 100,000 IU vitamin D3 supplementation over several years on cardiovascular events, respiratory infections, and falls/fractures. Participants provided information about recent kidney stone events in regular questionnaires sent to them with study capsules. Hospitalization data for kidney stones were collected from health authorities. Serum calcium was measured in an 8% subsample of participants who returned annually for blood tests. HRs of time to the first kidney stone event were calculated by Cox regression.

RESULTS

During a median follow-up of 3.3 y, 158 participants reported a kidney stone event (76 vitamin D, 82 placebo). The HR of reporting the first kidney stone event was 0.90 (95% CI: 0.66, 1.23; P = 0.51) for participants in the vitamin D arm compared with the placebo arm. There were 18 urolithiasis events in the hospitalization records: 7 in the vitamin D arm and 11 from the placebo arm. The HR to the first hospitalization urolithiasis event was 0.62 (95% CI: 0.24, 1.26; P = 0.30) in the vitamin D arm compared with the placebo arm. From the subsample annual blood test, there was no case of hypercalcemia in the vitamin D arm, compared with 1 in the placebo arm.

CONCLUSION

Over a median of 3.3 y, monthly supplementation with 100,000 IU vitamin D3 did not affect the incidence rate of kidney stone events, or hypercalcemia. This study was registered at clinicaltrials.gov as ACTRN12611000402943.

Association between serum 25-hydroxyvitamin D levels and self-reported chronic pain in older adults: A cross-sectional analysis from the ViDA study

Chronic pain is a major contributor to the global burden of disability. Prior studies on the association between serum 25-hydroxyvitamin D (25(OH)D) levels and chronic pain have yielded mixed results. The Vitamin D Assessment study, a large randomized controlled trial from New Zealand, offered the opportunity to examine this association in data collected at baseline in all participants, and among those with arthritis or depression. A total of 5110 participants aged 50-84 years were recruited from community general practices. Chronic pain (lasting ≥6 months) and other baseline characteristics were collected at baseline interview. Serum 25(OH)D concentration was measured by liquid chromatography-tandem mass spectrometry. Associations between 25(OH)D levels and chronic pain were explored using multivariable log-binomial regression to estimate relative risks (RRs). Out of 5049 participants with complete data, 871 (17%) reported having this clinical outcome, and 1254 (25%) had a 25(OH)D concentration <50 nmol/L. There was no significant association between 25(OH)D and chronic pain, with vitamin D status categorized in four groups: <25.0, 25.0-49.9, 50.0-74.9, and ≥75.0 nmol/L (the highest group as reference). The unadjusted RRs were 1.09, 1.10, and 1.08, respectively (P_trend = 0.24). Adjustment for demographics, lifestyle, BMI, medical history, prescription of analgesics and vitamin D supplements did not change this finding. Similar non-significant results were observed in participants with arthritis (n = 1732) or depression (n = 528). In this multi-ethnic, community-selected sample of older adults in New Zealand, serum 25(OH)D levels were not associated with chronic pain. These results do not support a role for low vitamin D status in the prevalence of chronic pain in older adults.

Adverse events from large dose vitamin D supplementation taken for one year or longer

In recent years, clinical trials increasingly have given large doses of vitamin D supplements to investigate possible health benefits beyond bone at high 25-hydroxyvitamin D levels. However, there are few publications on the safety of high-dose vitamin D given long term. The study objective was to investigate the cumulative relative risk (RR) of total adverse events, kidney stones, hypercalcemia and hypercalciuria from ≥2800 IU/d vitamin D₂ or D₃ supplementation, followed for one year or more in randomized controlled trials (RCTs). A systematic review was conducted in Medline Ovid, EMBASE and Cochrane in March 2018 to update results of studies published since a previous review in October 2015. RCTs were included if they gave vitamin D₂ or D₃ at ≥2800 IU/d for at least one year and reported on total adverse events or at least one calcium-related adverse event. There were a total of 32 studies that met the inclusion criteria. Of these, only 15 studies (3150 participants) reported one or more event of the outcomes of interest. Long-term high-dose vitamin D supplementation did not increase total adverse events compared to placebo in 1731 participants from 10 studies (RR = 1.05; 95% CI = 0.88, 1.24; p = 0.61), nor kidney stones in 1336 participants from 5 studies (RR = 1.26; 95% CI = 0.35, 4.58; p = 0.72). However, there was a trend for vitamin D to increase risk of hypercalcemia in 2598 participants from 10 studies (RR = 1.93; 95% CI = 1.00, 3.73; p = 0.05); while its effect on hypercalciuria in only 276 participants from 3 studies was inconclusive (RR = 1.93; 95% CI = 0.83, 4.46; p = 0.12). In conclusion, one year or longer supplementation with a large daily, weekly or monthly dose of vitamin D₂ /D₃ did not significantly increase a risk of total adverse events or kidney stones, although there was a trend towards increased hypercalcemia, and possibly for hypercalciuria.

Monthly high-dose vitamin D3 supplementation and self-reported adverse events in a 4-year randomized controlled trial

BACKGROUND

The use of high-dose vitamin D supplementation has increased in recent years. However, relatively little is known about the safety of long-term high doses.

AIMS

To investigate the safety of a monthly high-dose of vitamin D₃ supplementation taken for up to 4 years.

METHODS

Data were collected in a randomized, double blind, placebo-controlled trial of 5108 adults aged 50-84 years old from Auckland, New Zealand. Participants were given monthly doses of 100,000 IU vitamin D₃ or placebo, for a median of 3.3 years (range 2.5-4.2 years). They answered an open-ended question in a monthly questionnaire about any adverse events they attributed to the study capsules, which were coded blindly. Incidence rates per person months were calculated for categories of adverse events. Cox regression model used to calculate hazard ratio of time to first adverse-event.

RESULTS

In total, 419 (16.5%) participants taking vitamin D and 399 (15.8%) taking placebo reported ≥1 adverse event. Compared to placebo, the hazard ratio (HR) of reporting first adverse event in the vitamin D group was 1.03 (95% CI: 0.90, 1.18; p = 0.63). Despite a slightly higher incidence of recurrent adverse events in vitamin D arm, the incidence rate ratio (1.17) was not significantly higher in vitamin D (95% CI: 0.97, 1.41; p = 0.10). All regression results were adjusted for age, sex, and ethnicity. There was no difference between study arms in terms of participants' allocation perception (p = 0.52).

CONCLUSION

Monthly supplementation of 100,000 IU vitamin D3 for a median of 3.3 years did not affect participant-reported adverse events.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: ACTRN12611000402943; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=ACTRN12611000402943.

Hypercalcemia, hypercalciuria, and kidney stones in long-term studies of vitamin D supplementation: a systematic review and meta-analysis

BACKGROUND

Vitamin D supplementation is increasingly being used in higher doses in randomized controlled trials (RCTs). However, adverse events from very large annual doses of vitamin D have been shown in 2 RCTs, whereas in a third RCT, low-dose vitamin D, with calcium supplements, was shown to increase kidney stone risk.

OBJECTIVE

We analyzed the side effects related to calcium metabolism in RCTs, specifically hypercalcemia, hypercalciuria, and kidney stones, in participants who were given vitamin D supplements for ≥24 wk compared with in subjects in the placebo arm.

DESIGN

The following 3 main online databases were searched: Ovid Medline (PubMed), EMBASE, and the Cochrane Library. Software was used for the meta-analysis.

RESULTS

A total of 48 studies with 19,833 participants were identified, which reported ≥1 of the following side effects: hypercalcemia, hypercalciuria, or kidney stones. Of these studies, kidney stones were reported in only 9 trials with a tendency for fewer subjects reporting stones in the vitamin D arm than in the placebo arm (RR: 0.66, 95% CI: 0.41, 1.09; P = 0.10). In 37 studies, hypercalcemia was shown with increased risk shown for the vitamin D group (RR: 1.54; 95% CI: 1.09, 2.18; P = 0.01). Similar increased risk of hypercalciuria was shown in 14 studies for the vitamin D group (RR: 1.64; 95% CI: 1.06, 2.53; P = 0.03). In subgroup analyses, it was shown that the effect of vitamin D supplementation on risk of hypercalcemia, hypercalciuria, or kidney stones was not modified by baseline 25-hydroxyvitamin D, vitamin D dose and duration, or calcium co-supplementation.

CONCLUSIONS

Long-term vitamin D supplementation resulted in increased risks of hypercalcemia and hypercalciuria, which were not dose related. However, vitamin D supplementation did not increase risk of kidney stones. Additional large RCTs of long-term vitamin D supplementation are required to confirm these findings.

Effect of Vitamin D Supplementation on Pain: A Systematic Review and Meta-analysis

BACKGROUND

There is conflicting evidence from previous qualitative reviews on the effect of vitamin D supplementation on pain.

OBJECTIVE

To determine with quantitative methods if vitamin D supplementation lowers pain levels.

STUDY DESIGN

Quantitative meta-analysis of published randomized controlled trials (RCTs).

SETTING

This meta-analysis examined all studies involving the effect of vitamin D supplementation on pain score.

METHOD

Electronic sources (Medline, Embase, Cochrane Central Register of Controlled Trials, clinical trials website, and Google scholar) were systematically searched for RCTs of vitamin D supplementation and pain from inception of each database to October 2015.

RESULTS

Nineteen RCTs with 3,436 participants (1,780 on vitamin D supplementation and 1,656 on placebo) were included in the meta-analysis. For the primary outcome (mean change in pain score from baseline to final follow-up), 8 trials with 1,222 participants on vitamin D and 1,235 on placebo reported a significantly greater mean decrease in pain score for the vitamin D group compared to placebo (mean difference -0.57, 95% CI: -1.00 to -0.15, P = 0.007). The effect from vitamin D was greater in patients recruited with pre-existing pain (P-value for interaction = 0.03). Fourteen studies (1,548 on vitamin D, 1,430 on placebo) reported the mean pain score at final follow-up outcome, and no statistical difference was observed (mean difference -0.06, 95%CI: -0.44 to 0.33, P = 0.78). In 4 studies which reported pain improvement (209 on vitamin D, 146 on placebo), the effect size although not significant, shows participants in the vitamin D supplementation group were more likely to report pain improvement compared with the placebo group (relative risk 1.38, 95%CI: 0.93 to 2.05, P = 0.11).

LIMITATIONS

Only a few studies reported the mean score change from baseline to final follow-up, and we do not have enough data to determine any modifying effect of baseline vitamin D status and different doses of vitamin D supplementation on pain.

CONCLUSION

A significantly greater mean decrease in pain score (primary outcome) was observed with vitamin D supplementation compared with placebo in people with chronic pain. These results suggest that vitamin D supplementation could have a role in the management of chronic pain.

KEY WORDS

Meta-analysis, pain, randomized controlled trials, vitamin D supplementation.