Introduction
Thyrotoxic periodic paralysis (TPP) is a rare complication of thyrotoxicosis characterized by hypokalemia, and episodic muscle weakness/paralysis, which is potentially fatal when cardiopulmonary complications occur. The lack of large TPP cohorts hinders relevant epidemiology studies.
Aims
To establish a population-based registry of thyrotoxicosis and TPP in Hong Kong, and to evaluate their secular trend during 2002-2021.
Methods
Clinical data from the electronic medical database in Hong Kong, the Clinical Data Analysis and Reporting System (CDARS), was retrieved. One hundred potential cases of thyrotoxicosis (by ICD-9-CM: 242.xx) and TPP (by ICD-9-CM: 242.xx and 359.3, plus low potassium level) were randomly selected from CDARS, followed by reviewing clinical notes, examining laboratory test records, and deriving positive predictive value (PPV) of the clinical data. A population-based registry of thyrotoxicosis and TPP in Hong Kong was established. The standardized incidence rate of both thyrotoxicosis and TPP were computed with annual percentage change (APC) for trend analysis.
Results
The PPV of clinical data in CDARS for thyrotoxicosis and TPP were 0.86 (95% CI: 0.79-0.93) and 0.97 (95% CI: 0.94-1), respectively. Population-based cohorts of thyrotoxicosis (n=83,184) and TPP (n=999) were established. The age- and sex-standardized incidence rate of thyrotoxicosis increased from 45.22 to 80.7 per 100,000 person-years from 2002 to 2021, with APC of 4.72% (95% CI: 2.02-8.05). Both sexes had increasing trend in age-standardized incidence rate of thyrotoxicosis. As TPP patients were predominantly male, the age-standardized incidence rate of TPP was stratified in both sexes. In 2002 and 2021, the incidence rate (per 100,000 person-years) in male was 1.48 and 1.28 respectively, while that in female was 0.11 and 0.13, without significant trend observed.
Discussion
This is the first study validating clinical data for TPP in electronic medical database. Its high PPV enabled establishment of the largest TPP cohort to-date, facilitating future epidemiology studies.

Introduction: Psoriatic arthritis (PsA) poses a significant concern for patients with psoriasis. While previous studies have explored the impact of biological treatments on PsA progression, their ability to assess the effect of targeting specific interleukin (IL) pathways has been limited by insufficient statistical power.
Aims: To assess the risk of PsA associated with the use of IL-23 inhibitor (IL-23i), IL-17 inhibitor (IL-17i), or IL-12/23 inhibitor (IL-12/23i) compared to tumor necrosis factor inhibitor (TNFi) use among patients with psoriasis.
Methods: This population-based cohort study used the nationwide claims database from South Korea (2007–2022). New users of ILis or TNFis with psoriasis who did not have PsA or other inflammatory arthritis were categorized into each class of ILi use for comparison with TNFi use. The outcome was the development of PsA, assessed after a 3-month lag period to minimize protopathic bias. We calculated multinomial propensity scores and applied overlap weights to balance predifined covariates. Hazard ratio (HR) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models.
Results: We identified 9,681 patients with psoriasis (mean age 45.1; 33.7% female), of whom 3,913 (40.4%), 2,126 (22.0%), 2,773 (28.6%), and 909 (9.3%) were respectively exposed to IL-23i, IL-17i, IL-12/23i, and TNFi. PsA occurred in 276 (2.8%) patients during 23,045 person-years of follow-up. The weighted HR for any ILi was 0.43 (95% CI 0.28 – 0.68), with specific HRs of 0.25 (0.15 – 0.43), 0.52 (0.31 – 0.87), and 0.48 (0.30 – 0.76) for IL-23i, IL-17i, and IL-12/23i, respectively. IL-23is exhibited the greatest rate difference of -2.52 (-3.99 – -1.06) incident cases of PsA per 100 person-years.
Discussion: We found a reduced risk of PsA among patients with psoriasis using ILis, particularly IL-23is, compared to TNFis. These results support the current clinical practice, where newer ILis are the preferred biologics for managing psoriasis.

Introduction: Rare disease databases act as valuable sources of epidemiological data, treatment outcomes, and demographic spread of diseases. A comprehensive data source containing real-world information about the disease and corresponding treatment data can support informed decision-making, treatment management, and the development of targeted therapeutics. Due to vast demographic and social diversity, the Indian rare disease landscape is not well-studied and it is important to address this area through effective pharmacoepidemiological studies.
Aim: This review explores the current rare disease database scenario in the Indian context to identify the challenges associated with data collection and analysis and proposes solutions to address these to ensure effective database usage for rare disease treatment management.
Methods: A comprehensive search was undertaken to identify relevant studies on the quality, features, and utilization of rare disease databases in India. The studies were selected based on their relevance, information, and content that can either cover the Indian landscape or can be effectively extrapolated in the Indian context.
Results: The Indian healthcare system generates a vast amount of clinical information like clinical records, electronic health records, patient outcomes, clinician observation sheets, and insurance payout data. The Indian Council of Medical Research (ICMR) developed the National Registry for Rare and Other Inherited Disorders (NRROID) in 2019. This database can support epidemiological insight assessment, drug utilization studies, and effectiveness research. ~12,000 records have been aggregated so far, but challenges remain in source identification, infrastructure, awareness, and timely reporting.
Discussion: Rare disease databases can play crucial role in advancing pharmacoepidemiological research in India. By developing appropriate data capture and analysis mechanisms, fostering collaborations across researchers, clinicians, and companies, and promoting public-private partnerships in developing and implementing robust technological infrastructure, the rare disease treatment landscape can be vastly improved in India thus providing a better quality of life for rare disease patients.

Introduction: Research findings on the relationship between antipsychotics (AP) and cancer is oftentimes inconsistent across cancer sites and populations.
Aims: To estimate the incidence of site-specific cancer in patients who were first continuously prescribed antipsychotics in Hong Kong and compare it against the general population.
Methods: A descriptive, retrospective study was performed using real world data from Hong Kong Clinical Data Analysis and Reporting System (CDARS) and Hong Kong Cancer Registry (HKCaR). The crude incidence rate of cancer and age-standardized rate (ASR) were calculated to evaluate cancer incidence. Subgroup analyses were conducted for male and female users, as well as for first-generation antipsychotics (FGA) and second-generation antipsychotics (SGA) subgroups.
Results: For the AP users who were prescribed over 90 days or more would have more cancer risk than the general population (ASR of AP users vs ASR of general population (317.3 vs 249.1), the results reflected in all AP users and males (371.5 vs 268.7), females (275.9 vs 229.7), and FGA users (521.8 vs 249.1), but not true in SGA users (233.9 vs 249.1). The distribution of cancer among AP users exhibits both commonalities and distinct patterns compared to the general population. Major types of cancer among AP users rank similarly to those in the general population, indicating similarities in both male and female groups. Certain cancers such as lung, breast, leukaemia, and bladder cancers show higher ASR among AP users. Males have an additional higher risk of liver cancer incidence, and females have a relatively lower overall cancer risk, including a slightly reduced risk of lung cancer. Higher incidence of numerous cancer types is observed among FGA users compared with SGA users.
Conclusion: Incidence of cancer is higher among antipsychotic users compared to the general population, and the pattern of site-specific cancer incidence varied.

Background
Previous meta-analyses have linked aspirin use to a 20% reduction in both all-cause mortality and cancer-specific mortality. However, failing to account for immortal time bias might impede causal interpretation.
Objectives
To evaluate the effect of post-cancer diagnosis aspirin use on the overall mortality, cancer-specific mortality, and cardiovascular mortality.
Methods
We enrolled patients aged above 20 years old with newly diagnosed cancer between 2011 to 2018. We assigned the index date as the date of the first cancer diagnosis. The death record and the cause of death were obtained by linking with the National Death Registry. In the naïve analysis (i.e., subject to immortal time bias), aspirin use was defined as any prescription record after the index date. Thus, patients were inherently immortal during the period between the index date and the prescription date to allow for the use of aspirin. We then subsequently applied clone-censoring weighting (CCW) approaches to account for the immortal time bias. Outcomes were compared between patients who received aspirin within 365 days after the index date and those who did not. We used non-parametric bootstrap with 150 samplings to estimate the 95% confidence intervals.
Results
We identified a total of 41,662 cancer patients with a mean age of 64.7 (SD 16.5) and 56.62% male. In the entire follow-up period, 4,656 (11.2%) patients with any aspirin exposure, and the median time to prescription was 390 days. In the naïve analysis, post-cancer diagnosis use of aspirin was associated with protective effect against overall mortality (Hazard ratio: 0.83; 95% CI 0.79-0.88) and cancer-specific mortality (0.84; 0.74-0.95) and cardiovascular mortality (0.89; 0.73-1.00). However, using the CCW approach, no significant benefits were observed for overall mortality (1.05; 0.72-7.05), cancer-specific mortality (1.27; 0.89-92.78), and cardiovascular mortality (1.25; 0.89-43.83).
Conclusions
Protective effect of aspirin diminished after accounting for the immortal time bias.

Introduction: Systematic reviews and meta-analysis are reliable sources of clinical and medical evidences. However, in rapidly evolving medical fields, their relevance can quickly diminish without regular updates. Little research has been done on update frequency and shelf-life of systematic reviews.
Aims: To assess the frequency of updates and shelf-life of systematic reviews, to evaluate adherence to recommended update frequencies by different guidelines, and to compare the updating frequencies of academic vs industry-sponsored systematic reviews of poly (ADP-ribose) polymerase inhibitors (PARPi) in ovarian cancer (OC).
Methods: The study was registered in PROSPERO (ID: CRD42024509536) and conducted in accordance with PRISMA guidelines. A thorough search of PubMed and Cochrane Library databases (January 2015 - December 2023) was performed to identify systematic reviews of PARPi in OC. Relevant data were extracted, and shelf-life was determined using Kaplan-Meier analysis using Excel and SPSS version 29.0.2.0.
Results: Out of 115 systematic reviews, 43 met the inclusion criteria, with only 4.65% being updated. The median shelf-life for updating systematic reviews was 8 months due to new studies and 2 months due to new publications. The average time from search end date to acceptance of manuscript was 6 months, with publication taking an average of 10 months. Pharmaceutical companies sponsored fewer reviews compared to academia, with no significant difference in update frequency.
Conclusion: Half of the systematic reviews of PARPi in OC were outdated pre-publication, indicating non-adherence to existing guidelines. This underscores the urgency for enhanced updating protocols to uphold systematic review reliability.
Keywords: Systematic Review; Ovarian Cancer; PARP Inhibitors; Shelf-life.