Association between unstable diabetes mellitus and risk of pancreatic cancer.

BACKGROUND: Deterioration of glycaemic control in people with long-standing diabetes mellitus (diabetes) may be a possible indicator of pancreatic cancer. However, the magnitude of the association between diabetes deterioration and pancreatic cancer has received little attention. METHODS: We conducted a matched cohort study, nested within a population-based cohort of Australian women with diabetes. Women with unstable diabetes, defined as a change in medication after a 2-year period of stable medication use, were matched by birth year to those with stable diabetes, in a 1:4 ratio. We used flexible parametric survival models to estimate hazard ratios (HRs) and 95% confidence intervals (CI). RESULTS: We included 134,954 and 539,789 women in the unstable and stable diabetes cohorts, respectively (mean age 68 years). In total, 1,315 pancreatic cancers were diagnosed. Deterioration of stable diabetes was associated with a 2.5-fold increased risk of pancreatic cancer (HR 2.55; 95% CI 2.29-2.85). The risk was particularly high within the first year after diabetes deteriorated. HRs at 3 months, 6 months and 1 year were: 5.76 (95% CI 4.72-7.04); 4.56 (95% CI 3.81-5.46); and 3.33 (95% CI 2.86-3.89), respectively. The risk was no longer significantly different after 7 years. CONCLUSIONS: Deterioration in glycaemic control in people with previously stable diabetes may be an indicator of pancreatic cancer, suggesting investigations of the pancreas may be appropriate. The weaker longer-term (3-7 years) association between diabetes deterioration and pancreatic cancer may indicate that poor glycaemic control can be a risk factor for pancreatic cancer.

Hysterectomy with and without oophorectomy and all-cause and cause-specific mortality.

BACKGROUND: Hysterectomy is one of the most commonly performed gynecologic surgeries, with an estimated 30% of women in Australia undergoing the procedure by age of 70 years. In the United States, about 45% of women undergo hysterectomy in their lifetime. Some studies have suggested that this procedure increases the risk of premature mortality. With many women making the decision to undergo hysterectomy for a benign indication each year, additional research is needed to clarify whether there are long-term health consequences of hysterectomy. OBJECTIVE: This study aimed to examine the association between hysterectomy for benign indications, with or without removal of the ovaries, and cause-specific and all-cause mortality. STUDY DESIGN: Our cohort of 666,588 women comprised the female population of Western Australia with linked hospital and health records from 1970 to 2015. Cox regression models were used to assess the association between hysterectomy and all-cause, cardiovascular disease, cancer, and other mortality by oophorectomy type (categorized as none, unilateral, and bilateral), with no hysterectomy or oophorectomy as the reference group. We repeated these analyses using hysterectomy without oophorectomy as the reference group. We also investigated whether associations varied by age at the time of surgery, although small sample size precluded this analysis in women who underwent hysterectomy with unilateral salpingo-oophorectomy. In our main analysis, women who underwent hysterectomy or oophorectomy as part of cancer treatment were retained in the analysis and considered unexposed to that surgery. For a sensitivity analysis, we censored procedures performed for cancer. RESULTS: Compared with no surgery, hysterectomy without oophorectomy before 35 years was associated with an increase in all-cause mortality (hazard ratio, 1.29; 95% confidence interval, 1.19-1.40); for surgery after 35 years of age, there was an inverse association (35-44 years: hazard ratio, 0.93; 95% confidence interval, 0.89-0.97). Similarly, hysterectomy with bilateral salpingo-oophorectomy before 45 years of age was associated with increased all-cause mortality (35-44 years: hazard ratio, 1.15; 95% confidence interval, 1.04-1.27), but decreased mortality rates after 45 years of age. In our sensitivity analysis, censoring gynecologic surgeries for cancer resulted in many cancer-related deaths being excluded for women who did not have surgery for benign indications and thus increased the hazard ratios for the associations between both hysterectomy without oophorectomy and hysterectomy with bilateral salpingo-oophorectomy and risk of all-cause and cancer-specific mortality. The sensitivity analysis therefore potentially biased the results in favor of no surgery. CONCLUSION: Among women having surgery for benign indications, hysterectomy without oophorectomy performed before 35 years of age and hysterectomy with bilateral salpingo-oophorectomy performed before 45 years of age were associated with an increase in all-cause mortality. These procedures are not associated with poorer long-term survival when performed at older ages.

Value of Pathology Review in a Population-based Series of Ovarian Tumors.

Ovarian neoplasia comprises a heterogenous group of tumors with distinct clinicopathologic and molecular features and therefore assessment of potential risk factors should be tumor subtype specific. As part of ongoing epidemiological investigations of ovarian neoplasia in Western Australia, we performed an initial review of original pathology reports followed, in selected cases, by reassessment of histology material to optimize accurate diagnosis. Additional immunohistochemistry, often using antibodies unavailable at the time of initial assessment, was also performed as required. From an initial cohort of 1660 cases identified through the Western Australia Cancer Registry, benign, nonepithelial, nonovarian, miscellaneous, and indeterminate cases were excluded. Also excluded were 33 cases that were reclassified as ovarian metastases rather than primary ovarian tumors. Following exclusions there remained 1321 borderline and malignant epithelial neoplasms. The diagnosis was considered accurate in 1186 cases (89.8%) based upon information in the initial pathology reports and clinical follow-up data but uncertain in 135 cases (10.2%). Histologic review was possible in 92 of the latter tumors leading to an amended diagnosis in 63 cases (68.5%). The most common types of diagnostic amendment were the reclassification of high-grade carcinomas of undifferentiated, endometrioid, or transitional appearance as high-grade serous carcinoma, and the reclassification of most carcinomas of mixed epithelial type as "pure" carcinomas. This review illustrated specific pitfalls in the diagnosis of ovarian epithelial neoplasia and helped to maintain the accuracy of the Western Australia Cancer Registry. Accurate diagnosis will optimize further epidemiological studies assessing risk factors in specific subtypes of ovarian neoplasia.

Declining rates of sterilisation reversal procedures in western Australian women from 1990 to 2008: the relationship with age, hospital type and government policy changes.

BACKGROUND: Female sterilisation is usually performed on an elective basis at perceived family completion, however, around 1-3% of women who have undergone sterilisation elect to undergo sterilisation reversal (SR) at a later stage. The trends in SR rates in Western Australia (WA), proportions of SR procedures between hospital types (public and private), and the effects of Federal Government policies on these trends are unknown. METHODS: Using records from statutory state-wide data collections of hospital separations and births, we conducted a retrospective descriptive study of all women aged 15-49 years who underwent a SR procedure during the period 1st January 1990 to 31st December 2008 (n = 1868 procedures). RESULTS: From 1991 to 2007 the annual incidence rate of SR procedures per 10,000 women declined from 47.0 to 3.6. Logistic regression modelling showed that from 1997 to 2001 the odds of women undergoing SR in a private hospital as opposed to all other hospitals were 1.39 times higher (95% CI 1.07-1.81) and 7.51 times higher (95% CI 5.46-10.31) from 2002 to 2008. There were significant decreases in SR rates overall and among different age groups after the Federal Government interventions. CONCLUSION: Rates of SR procedures in WA have declined from 1990 to 2008, particularly following policy changes such as the introduction of private health insurance (PHI) policies. This suggests decisions to undergo SR may be influenced by Federal Government interventions.

A comparison of multivariate and univariate time series approaches to modelling and forecasting emergency department demand in Western Australia.

OBJECTIVE: To develop multivariate vector-ARMA (VARMA) forecast models for predicting emergency department (ED) demand in Western Australia (WA) and compare them to the benchmark univariate autoregressive moving average (ARMA) and Winters' models. METHODS: Seven-year monthly WA state-wide public hospital ED presentation data from 2006/07 to 2012/13 were modelled. Graphical and VARMA modelling methods were used for descriptive analysis and model fitting. The VARMA models were compared to the benchmark univariate ARMA and Winters' models to determine their accuracy to predict ED demand. The best models were evaluated by using error correction methods for accuracy. RESULTS: Descriptive analysis of all the dependent variables showed an increasing pattern of ED use with seasonal trends over time. The VARMA models provided a more precise and accurate forecast with smaller confidence intervals and better measures of accuracy in predicting ED demand in WA than the ARMA and Winters' method. CONCLUSION: VARMA models are a reliable forecasting method to predict ED demand for strategic planning and resource allocation. While the ARMA models are a closely competing alternative, they under-estimated future ED demand.

In vitro fertilization is associated with an increased risk of borderline ovarian tumours.

OBJECTIVES: To compare the risk of borderline ovarian tumours in women having in vitro fertilization (IVF) with women diagnosed with infertility but not having IVF. METHODS: This was a whole-population cohort study of women aged 20-44 years seeking hospital infertility treatment or investigation in Western Australia in 1982-2002. Using Cox regression, we examined the effects of IVF treatment and potential confounders on the rate of borderline ovarian tumours. Potential confounders included parity, age, calendar year, socio-economic status, infertility diagnoses including pelvic inflammatory disorders and endometriosis and surgical procedures including hysterectomy and tubal ligation. RESULTS: Women undergoing IVF had an increased rate of borderline ovarian tumours with a hazard ratio (HR) of 2.46 (95% confidence interval [CI] 1.20-5.04). Unlike invasive epithelial ovarian cancer, neither birth (HR 0.89; 95% CI 0.43-1.88) nor hysterectomy (1.02; 0.24-4.37) nor sterilization (1.48; 0.63-3.48) appeared protective and the rate was not increased in women with a diagnosis of endometriosis (HR 0.31; 95% CI 0.04-2.29). CONCLUSIONS: Women undergoing IVF treatment are at increased risk of being diagnosed with borderline ovarian tumours. Risk factors for borderline ovarian tumours appear different from those for invasive ovarian cancer.

In vitro fertilization, endometriosis, nulliparity and ovarian cancer risk.

OBJECTIVES: To examine the risk of invasive epithelial ovarian cancer in a cohort of women seeking treatment for infertility. METHODS: Using whole-population linked hospital and registry data, we conducted a cohort study of 21,646 women commencing hospital investigation and treatment for infertility in Western Australia in the years 1982-2002. We examined the effects of IVF treatment, endometriosis and parity on risk of ovarian cancer and explored potential confounding by tubal ligation, hysterectomy and unilateral oophorectomy/salpingo-oophorectomy (USO). RESULTS: Parous women undergoing IVF had no observable increase in the rate of ovarian cancer (hazard ratio [HR] 1.01; 95% confidence interval [CI] 0.35-2.90); the HR in women who had IVF and remained nulliparous was 1.76 (95% CI 0.74-4.16). Women diagnosed with endometriosis who remained nulliparous had a three-fold increase in the rate of ovarian cancer (HR 3.11; 95% CI 1.13-8.57); the HR in parous women was 1.52 (95% CI 0.34-6.75). In separate analyses, women who had a USO without hysterectomy had a four-fold increase in the rate of ovarian cancer (HR 4.23; 95% CI 1.30-13.77). Hysterectomy with or without USO appeared protective. CONCLUSIONS: There is no evidence of an increased risk of ovarian cancer following IVF in women who give birth. There is some uncertainty regarding the effect of IVF in women who remain nulliparous. Parous women diagnosed with endometriosis may have a slightly increased risk of ovarian cancer; nulliparous women have a marked increase in risk.

Perioperative Beta-Blocker Supply and Survival in Women With Epithelial Ovarian Cancer and a History of Cardiovascular Conditions.

PURPOSE: Surgery for epithelial ovarian cancer (EOC) may activate stress-inflammatory responses that stimulate tumor growth and increase metastatic growth. Animal and in vitro studies have shown that inhibition of the catecholamine-induced inflammatory response via beta-adrenergic receptor blockade has antitumor potential in EOC. However, observational studies have reported mixed results. We assessed whether beta-blocker (BB) use at the time of primary ovarian cancer surgery was associated with improved survival in a large population-based study. MATERIALS AND METHODS: Using linked administrative data, a population-based cohort of 3,844 Australian women age 50 years or older with a history of cardiovascular conditions who underwent surgery for EOC was followed for survival outcomes. The average treatment effect of selective BB (SBB) and nonselective BB (NSBB) supply at the time of surgery on survival was estimated from a causal inference perspective using covariate-balanced inverse probability of treatment weights with flexible parametric survival models that allowed for time-varying survival effects. RESULTS: Around the time of surgery, 560 (14.5%) women were supplied a SBB and 67 (1.7%) were supplied a NSBB. At 2 years postsurgery, the survival proportion was 80% (95% CI, 68 to 88) for women dispensed NSBBs at surgery compared with 69% (95% CI, 67 to 70) for women not supplied NSBBs. The survival advantage appeared to extend to at least 8 years postsurgery. No association was observed for women dispensed a SBB around the time of surgery. CONCLUSION: Perioperative supply of NSBBs appeared to confer a survival advantage for women age over 50 years with a history of cardiovascular conditions. Long-term clinical trials are required to confirm these findings.

Association between antihypertensive medicine use and risk of ovarian cancer in women aged 50 years and older.

BACKGROUND: Epithelial ovarian cancer (EOC) has few modifiable risk factors. There is evidence that some antihypertensive medicines may have cancer preventive and/or therapeutic actions; therefore, we assessed the associations between use of different antihypertensive medicines and risk of specific EOC histotypes. METHODS: Our nested case-control study of linked administrative health data included 6070 Australian women aged over 50 years diagnosed with EOC from 2004 to 2013, and 30,337 matched controls. We used multivariable conditional logistic regression to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) for the association between ever use of each antihypertensive medicine group, including beta-adrenergic blockers, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, diuretics, and alpha blockers, and the risk of EOC overall and separately for the serous, endometrioid, mucinous, clear cell and other histotypes. RESULTS: We found that most antihypertensive medicines were not associated with risk of EOC. However, women who used calcium channel blockers had a reduced risk of serous EOC (OR= 0.89, 95 % CI:0.81,0.98) and use of combination thiazide and potassium-sparing diuretics was associated with an increased risk of endometroid EOC (OR= 2.09, 95 % CI:1.15,3.82). CONCLUSION: Our results provide little support for a chemo-preventive role for most antihypertensives, however, the histotype-specific associations we found warrant further investigation.

Nitrogen-based Bisphosphonate Use and Ovarian Cancer Risk in Women Aged 50 Years and Older.

BACKGROUND: There are few readily modifiable risk factors for epithelial ovarian cancer; preclinical studies suggest bisphosphonates could have chemopreventive actions. Our study aimed to assess the association between use of nitrogen-based bisphosphonate medicine and risk of epithelial ovarian cancer, overall and by histotype. METHODS: We conducted a case-control study nested within a large, linked administrative dataset including all Australian women enrolled for Medicare, Australia's universal health insurance scheme, between July 2002 and December 2013. We included all women with epithelial ovarian cancer diagnosed at age 50 years and older between July 1, 2004, and December 31, 2013 (n = 9367) and randomly selected up to 5 controls per case, individually matched to cases by age, state of residence, area-level socioeconomic status, and remoteness of residence category (n = 46 830). We used prescription records to ascertain use of nitrogen-based bisphosphonates (ever use and duration of use), raloxifene, and other osteoporosis medicines (no nitrogen-based bisphosphonates, strontium and denosumab). We calculated adjusted odds ratios (OR) and 95% confidence intervals (CI) using conditional logistic regression. RESULTS: Ever use of nitrogen-based bisphosphonates was associated with a reduced risk of epithelial ovarian cancer compared with no use (OR = 0.81, 95% CI = 0.75 to 0.88). There was a reduced risk of endometrioid (OR = 0.51, 95% CI = 0.33 to 0.79) and serous histotypes (OR = 0.84, 95% CI = 0.75 to 0.93) but no association with the mucinous or clear cell histotypes. CONCLUSION: Use of nitrogen-based bisphosphonates was associated with a reduced risk of endometrioid and serous ovarian cancer. This suggests the potential for use for prevention, although validation of our findings is required.

The association between diabetes mellitus of different durations and risk of pancreatic cancer: an Australian national data-linkage study in women.

AIMS: The bidirectional association between diabetes mellitus (DM) and pancreatic cancer (PC) is established; however, the strength of association between duration of DM and risk of PC needs further investigation. METHODS: We conducted a case-control study nested within a population-based cohort of Australian women established using record linkage. Women diagnosed with PC from July 2007 to December 2013, were matched to five controls based on age and state of residence. DM was defined according to prescription of anti-diabetic medication from administrative prescription data. We used conditional logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI), adjusted for area-level socioeconomic status, rurality of residence, weighted comorbidity score, and predicted probability of obesity. RESULTS: The analyses included 7,267 cases and 35,978 controls. The mean age at the time of DM diagnosis was 71 years whereas the mean age at the time of diagnosis of PC was 76 years. A history of DM of any duration was associated with a 2-fold increase in risk of PC (OR=2.12; 95%CI:1.96-2.29) compared to having no history of DM. The risk decreased with increasing duration of DM. The highest risk was in those who had recent-onset DM (OR=8.08; 95%CI:6.88-9.50 for <12 months of DM), but the risk remained elevated with ≥5 years of DM (OR=1.40; 95%CI:1.27-1.55). CONCLUSION: The markedly increased risk of PC in those with recent-onset DM emphasises the need for further research to distinguish patients for whom new-onset DM is a manifestation of PC from those with type-2 DM. The elevated risk associated with long-standing DM suggests that preventing DM may contribute to a reduction in the incidence of PC.

Hysterectomy and Risk of Breast, Colorectal, Thyroid, and Kidney Cancer - an Australian Data Linkage Study.

BACKGROUND: This study aimed to investigate the associations between hysterectomy for benign indications and risk of breast, colorectal, kidney, and thyroid cancer, and to explore whether these associations are modified by removal of ovaries at the time of surgery or by age at surgery. METHODS: We conducted a retrospective cohort study of the female population of Western Australia (n = 839,332) linking data from electoral, hospital, births, deaths, and cancer records. We used Cox regression to estimate HRs and 95% confidence intervals (CI) for the associations between hysterectomy and diagnosis of breast, colorectal, kidney, and thyroid cancers. RESULTS: Compared with no surgery, hysterectomy without oophorectomy (hysterectomy) and hysterectomy with bilateral salpingo-oophorectomy (hysterectomy-BSO) were associated with higher risk of kidney cancer (HR, 1.32; 95% CI, 1.11-1.56 and HR, 1.29; 95% CI, 0.96-1.73, respectively). Hysterectomy, but not hysterectomy-BSO, was related to higher risk of thyroid cancer (HR, 1.38; 95% CI, 1.19-1.60). In contrast, hysterectomy (HR, 0.94; 95% CI, 0.90-0.98) and hysterectomy-BSO (HR, 0.92; 95% CI, 0.85-1.00) were associated with lower risk of breast cancer. We found no association between hysterectomy status and colorectal cancer. CONCLUSIONS: The associations between hysterectomy and cancer varied by cancer type with increased risks for thyroid and kidney cancer, decreased risk for breast cancer, and no association for colorectal cancer. IMPACT: As breast, colorectal, and gynecologic cancers comprise a sizeable proportion of all cancers in women, our results suggest that hysterectomy is unlikely to increase overall cancer risk; however, further research to understand the higher risk of thyroid and kidney cancer is warranted.

The Association Between Hysterectomy and Ovarian Cancer Risk: A Population-Based Record-Linkage Study.

BACKGROUND: Recent studies have called into question the long-held belief that hysterectomy without oophorectomy protects against ovarian cancer. This population-based longitudinal record-linkage study aimed to explore this relationship, overall and by age at hysterectomy, time period, surgery type, and indication for hysterectomy. METHODS: We followed the female adult Western Australian population (837 942 women) across a 27-year period using linked electoral, hospital, births, deaths, and cancer records. Surgery dates were determined from hospital records, and ovarian cancer diagnoses (n = 1640) were ascertained from cancer registry records. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between hysterectomy and ovarian cancer incidence. RESULTS: Hysterectomy without oophorectomy (n = 78 594) was not associated with risk of invasive ovarian cancer overall (HR = 0.98, 95% CI = 0.85 to 1.11) or with the most common serous subtype (HR = 1.05, 95% CI = 0.89 to 1.23). Estimates did not vary statistically significantly by age at procedure, time period, or surgical approach. However, among women with endometriosis (5.8%) or with fibroids (5.7%), hysterectomy was associated with substantially decreased ovarian cancer risk overall (HR = 0.17, 95% CI = 0.12 to 0.24, and HR = 0.27, 95% CI = 0.20 to 0.36, respectively) and across all subtypes. CONCLUSIONS: Our results suggest that for most women, having a hysterectomy with ovarian conservation is not likely to substantially alter their risk of developing ovarian cancer. However, our results, if confirmed, suggest that ovarian cancer risk reduction could be considered as a possible benefit of hysterectomy when making decisions about surgical management of endometriosis or fibroids.

Risk of high-grade serous ovarian cancer associated with pelvic inflammatory disease, parity and breast cancer.

BACKGROUND: Ovarian carcinoma is not a single disease, but rather a collection of subtypes with differing molecular properties and risk profiles. The most common of these, and the subject of this work, is high-grade serous ovarian carcinoma (HGSC). METHODS: In this population-based study we identified a cohort of 441,382 women resident in Western Australia who had ever been admitted to hospital in the State. Of these, 454 were diagnosed with HGSC. We used Cox regression to derive hazard ratios (HRs) comparing the risk of disease in women who had each of a range of medical diagnoses and surgical procedures with women who did not. RESULTS: We found an increased risk of HGSC associated with a diagnosis of pelvic inflammatory disease (PID) (HR 1.47, 95% CI 1.04-2.07) but not with a diagnosis of infertility or endometriosis with HRs of 1.12 (95% CI 0.73-1.71) and 0.82 (95% CI 0.55-1.22) respectively. A personal history of breast cancer was associated with a three-fold increase in the rate of HGSC. Increased parity was associated with a reduced risk of HGSC in women without a personal history of breast cancer (HR 0.57; 95% CI 0.44-0.73), but not in women with a personal history of breast cancer (HR 1.48; 95% CI 0.74-2.95). CONCLUSIONS: Our finding of an increased risk of HGSC associated with PID lends support to the hypothesis that inflammatory processes may be involved in the etiology of HGSC.

Declining rates of sterilization procedures in Western Australian women from 1990 to 2008: the relationship with age, hospital type, and government policy changes.

OBJECTIVE: To describe trends in age-specific incidence rates of female sterilization (FS) procedures in Western Australia and to evaluate the effects of the introduction of government-subsidized contraceptive methods and the implementation of the Australian government's baby bonus policy on FS rates. DESIGN: Population-based retrospective descriptive study. SETTING: Not applicable. PATIENT(S): All women ages 15-49 undergoing an FS procedure during the period January 1, 1990, to December 31, 2008 (n = 47,360 procedures). INTERVENTION(S): Records from statutory statewide data collections of hospitals separations and births were extracted and linked. MAIN OUTCOME MEASURE(S): Trends in FS procedures and the influence on these trends of the introduction of government policies: subsidization of long-acting reversible contraceptives (Implanon and Mirena) and the Australian baby bonus initiative. RESULT(S): The annual incidence rate of FS procedures declined from 756.9 per 100,000 women in 1990 to 155.2 per 100,000 women in 2008. Compared with the period 1990-1994, women ages 30-39 years were 47% less likely (rate ratio [RR] = 0.53; 95% confidence interval [CI], 0.39-0.72) to undergo sterilization during the period 2005-2008. Adjusting for overall trend, there were significant decreases in FS rates after government subsidization of Implanon (RR = 0.89; 95% CI, 0.82-0.97) and Mirena (RR = 0.81; 95% CI, 0.73-0.91) and the introduction of the baby bonus (RR = 0.70; 95% CI, 0.61-0.81). CONCLUSION(S): Rates of female sterilization procedures in Western Australia have declined substantially across all age groups in the last two decades. Women's decisions to undergo sterilization procedures may be influenced by government interventions that increase access to long-term reversible contraceptives or encourage childbirth.

Growth in Western Australian emergency department demand during 2007-2013 is due to people with urgent and complex care needs.

OBJECTIVES: To determine the magnitude and characteristics of the increase in ED demand in Western Australia (WA) from 2007 to 2013. METHODS: We conducted a population-based longitudinal study examining trends in ED demand, stratified by area of residence, age group, sex, Australasian Triage Scale category and discharge disposition. The outcome measures were annual number and rate of ED presentations. We calculated average annual growth, and age-specific and age-standardised rates. We assessed the statistical significance of trends, overall and within each category, using the Mann-Kendall trend test and analysis of variance ANOVA. We also calculated the proportions of growth in ED demand that were attributable to changes in population and utilisation rate. RESULTS: From 2007 to 2013, ED presentations increased by an average 4.6% annually from 739,742 to 945,244. The rate increased 1.4% from 354.1 to 382.6 per 1000 WA population (P = 0.02 for the trend). The main increase occurred in metropolitan WA, age 45+ years, triage category 2 and 3 and admitted cohorts. Approximately three-quarters of this increase was due to population change (growth and ageing) and one-quarter due to increase in utilisation. CONCLUSION: Our study reveals a 4.6% annual increase in ED demand in WA in 2007-2013, mostly because of an increase in people with urgent and complex care needs, and not a shift (demand transfer) from primary care. This indicates that a system-wide integrated approach is required for demand management.

Hospital mental health admissions in women after unsuccessful infertility treatment and in vitro fertilization: an Australian population-based cohort study.

OBJECTIVE: To examine the association between in vitro fertilization (IVF) and later admission to hospital with a mental health diagnosis in women who remained childless after infertility treatment. METHODS: This was a population-based cohort study using linked administrative hospital and registry data. The study population included all women commencing hospital treatment for infertility in Western Australia between the years 1982 and 2002 aged 20-44 years at treatment commencement who did not have a recorded birth by the end of follow-up (15 August 2010) and did not have a hospital mental health admission prior to the first infertility admission (n=6,567). Of these, 2,623 women had IVF and 3,944 did not. We used multivariate Cox regression modeling of mental health admissions and compared women undergoing IVF treatment with women having infertility treatment but not IVF. RESULTS: Over an average of 17 years of follow-up, 411 women in the cohort were admitted to hospital with a mental health diagnosis; 93 who had IVF and 318 who did not. The unadjusted hazard ratio (HR) for a hospital mental health admission comparing women who had IVF with those receiving other infertility treatment was 0.50 (95% confidence interval [CI] 0.40-0.63). After adjustment for age, calendar year and socio-economic status the HR was 0.56 (95% CI 0.44-0.71). CONCLUSIONS: IVF treatment is associated with a reduced risk of hospital mental health admissions in women after unsuccessful infertility treatment. This may be explained by the healthy cohort effect.

Association between in-vitro fertilization, birth and melanoma.

A link between reproductive hormones and melanoma has long been suspected, and has been examined for numerous hormonal exposures, but the association between in-vitro fertilization (IVF) and melanoma has not been studied in depth. We used whole-population linked hospital and registry data to carry out a cohort study of women aged 20-44 years seeking hospital investigation and treatment for infertility in Western Australia from 1982 to 2002 with follow-up to 2010. The cohort comprised a total of 21 604 women followed for an average of 17.2 years. Of these, 7524 had IVF treatment, 14 870 gave birth and 149 women were diagnosed with an incident invasive melanoma. Using Cox regression analysis, we estimated hazard ratios (HRs) for melanoma associated with IVF and parity. Women who had IVF and gave birth had an increased rate of invasive melanoma compared with women who had IVF and remained nulliparous (HR 3.61; 95% confidence interval 1.79-7.26). There was little or no increase in the rate of invasive melanoma associated with giving birth in women who had non-IVF infertility treatment (HR 1.39; 95% confidence interval 0.88-2.20). These results suggest an association between reproductive factors and melanoma in the subgroup of women undergoing IVF treatment.