Lag Interval Research Articles

Comparison for the effects of different components of temperature variability on mortality: A multi-country time-series study

BackgroundTemperature variability (TV) is associated with increased mortality risk. However, it is still unknown whether intra-day or inter-day TV has different effects. ObjectivesWe aimed to assess the association of intra-day TV and inter-day TV with all-cause, cardiovascular, and respiratory mortality. MethodsWe collected data on total, cardiovascular, and respiratory mortality and meteorology from 758 locations in 47 countries or regions from 1972 to 2020. We defined inter-day TV as the standard deviation (SD) of daily mean temperatures across the lag interval, and intra-day TV as the average SD of minimum and maximum temperatures on each day. In the first stage, inter-day and intra-day TVs were modelled simultaneously in the quasi-Poisson time-series model for each location. In the second stage, a multi-level analysis was used to pool the location-specific estimates. ResultsOverall, the mortality risk due to each interquartile range [IQR] increase was higher for intra-day TV than for inter-day TV. The risk increased by 0.59% (95% confidence interval [CI]: 0.53, 0.65) for all-cause mortality, 0.64% (95% CI: 0.56, 0.73) for cardiovascular mortality, and 0.65% (95% CI: 0.49, 0.80) for respiratory mortality per IQR increase in intra-day TV0–7 (0.9 °C). An IQR increase in inter-day TV0–7 (1.6 °C) was associated with 0.22% (95% CI: 0.18, 0.26) increase in all-cause mortality, 0.44% (95% CI: 0.37, 0.50) increase in cardiovascular mortality, and 0.31% (95% CI: 0.21, 0.41) increase in respiratory mortality. The proportion of all-cause deaths attributable to intra-day TV0–7 and inter-day TV0–7 was 1.45% and 0.35%, respectively. The mortality risks varied by lag interval, climate area, season, and climate type. ConclusionsOur results indicated that intra-day TV may explain the main part of the mortality risk related to TV and suggested that comprehensive evaluations should be proposed in more countries to help protect human health.

Decision for Carpal Tunnel Surgery: High-deductible Health Plans versus Traditional Health Plans.

Delay in surgical treatment for carpal tunnel syndrome (CTS) may result in long-term decreased functional outcomes. Few investigators have examined the relationship between type of health insurance plan and time to definitive treatment of CTS following diagnosis. We investigated the relationship between insurance type, treatment decision, and the time between diagnosis and surgery across groups. This was a retrospective cohort study using the MarketScan Commercial Claims and Encounters Database 2011-2020. We used χ2 tests, linear regression, and logistic regression models to analyze demographic data and the time lag interval between CTS diagnosis and treatment. Overall, 28% of high-deductible health plan (HDHP) patients underwent carpal tunnel release, compared with 20% of traditional insurance patients (P < 0.001). HDHPs are defined by the internal revenue service as a deductible of $1400 for an individual or $2800 for a family per year. The odds of undergoing surgery versus no treatment for HDHP patients were 47% higher than traditional patients (P < 0.001). Among the patients who underwent surgery, HDHP patients underwent surgery 65 days earlier on average following diagnosis compared with traditional patients (P < 0.001). Patients with HDHPs who receive a diagnosis of CTS are more likely to undergo surgery, with a shorter time lag between diagnosis and surgery. The results from this study call attention to differences in surgical decision-making between patients enrolled in different insurance plans.

Methods for early characterisation of the severity and dynamics of SARS-CoV-2 variants: a population-based time series analysis in South Africa

BackgroundAssessment of disease severity associated with a novel pathogen or variant provides crucial information needed by public health agencies and governments to develop appropriate responses. The SARS-CoV-2 omicron variant of concern (VOC) spread rapidly through populations worldwide before robust epidemiological and laboratory data were available to investigate its relative severity. Here we develop a set of methods that make use of non-linked, aggregate data to promptly estimate the severity of a novel variant, compare its characteristics with those of previous VOCs, and inform data-driven public health responses.MethodsUsing daily population-level surveillance data from the National Institute for Communicable Diseases in South Africa (March 2, 2020, to Jan 28, 2022), we determined lag intervals most consistent with time from case ascertainment to hospital admission and within-hospital death through optimisation of the distance correlation coefficient in a time series analysis. We then used these intervals to estimate and compare age-stratified case-hospitalisation and case-fatality ratios across the four epidemic waves that South Africa has faced, each dominated by a different variant.FindingsA total of 3 569 621 cases, 494 186 hospitalisations, and 99 954 deaths attributable to COVID-19 were included in the analyses. We found that lag intervals and disease severity were dependent on age and variant. At an aggregate level, fluctuations in cases were generally followed by a similar trend in hospitalisations within 7 days and deaths within 15 days. We noted a marked reduction in disease severity throughout the omicron period relative to previous waves (age-standardised case-fatality ratios were consistently reduced by >50%), most substantial for age strata with individuals 50 years or older.InterpretationThis population-level time series analysis method, which calculates an optimal lag interval that is then used to inform the numerator of severity metrics including the case-hospitalisation and case-fatality ratio, provides useful and timely estimates of the relative effects of novel SARS-CoV-2 VOCs, especially for application in settings where resources are limited.FundingNational Institute for Communicable Diseases of South Africa, South African National Government.

The Impact of Saharan Dust on Visits to Clinics in Antigua and Barbuda for Acute Respiratory Infections

At present there is no assessment of the health impacts of Saharan dust in Antigua and Barbuda. A retrospective study was conducted to determine the association between Saharan dust particles along with other climatic variables and visits to the clinics for acute respiratory infections. All visits to the clinics on both islands (n=8851) over 14 years (1999-2003, 2005, 2011-2018) were compared to the dust haze observations and climatic variables using regression analysis. A negative correlation was observed between visits to clinics for acute respiratory infections (ARIs) and the presence of dust haze in the atmosphere (R2 =0.339, p=0.029). Visits for ARIs had positive correlations with wind speed (R2 =0.373, p=0.020), mean sea level pressure (R2 =0.094, p=0.286), relative humidity (R2 =0.203, p=0.106) and rainfall (R2 =0.040, p=0.493). A significant inverse relationship was found between visits and the study years (R2 =0.666, p=&lt;0.001). Saharan dust impacts the residents of Antigua and Barbuda causing an increase in visits to clinics for ARIs with a lag or latency interval between the dust events. These findings provide good evidence which should aid governments in planning their strategic response to this serious public health issue.

Continuous-Time Modeling of the Bidirectional Relationship Between Incidental Affect and Physical Activity.

Previous research suggests that there is a bidirectional relationship between incidental affect (i.e., how people feel in day-to-day life) and physical activity behavior. However, many inconsistencies exist in the body of work due to the lag interval between affect and physical activity measurements. Using a novel continuous-time analysis paradigm, we examined the temporal specificity underlying the dynamic relationship between positive and negative incidental affective states and moderate-to-vigorous physical activity (MVPA). A community sample of adults (n = 126, Mage = 27.71, 51.6% Male) completed a 14-day ambulatory assessment protocol measuring momentary positive and negative incidental affect six times a day while wearing a physical activity monitor (Fitbit). Hierarchical Bayesian continuous-time structural equation modeling was used to elucidate the underlying dynamics of the relationship between incidental affective states and MVPA. Based on the continuous-time cross-effects, positive and negative incidental affect predicted subsequent MVPA. Furthermore, engaging in MVPA predicted subsequent positive and negative incidental affect. Incidental affective states had a greater relative influence on predicting subsequent MVPA compared to the reciprocal relationship. Analysis of the discrete-time coefficients suggests that cross-lagged effects increase as the time interval between measurements increase, peaking at about 8 h between measurement occasions before beginning to dissipate. The results provide support for a recursive relationship between incidental affective states and MVPA, which is particularly strong at 7-9 hr time intervals. Future research designs should consider these medium-term dynamics, for both theory development and intervention.

Contemporary Technologies in Chronopharmaceutic Drug Delivery System

Traditional drug delivery methods aimed for a consistent or sustained medication output to maximize treatment efficacy while minimizing side effects. These dosage forms release medications in a controlled or varied manner. Illnesses are treated by administering drugs to patients in a variety of traditional dose patterns. All these dosage patterns should always be administered monotonously for retaining the drug concentration in a therapeutically effective spectrum. Chronotherapeutics, a type of drug delivery system, has become increasingly important in the treatment of chronic diseases in recent years. Today's environment necessitates chronopharmaceutical formulations that increase patient compliance, optimize medicine distribution at the target site, and minimize side effects to reduce mortality rates. A mechanism in which a medicament has been distributed rapidly after a specified lag interval or time gap in compliance with the circadian rhythm of sickness conditions is known as pulsative drug release. Pulsatile medication delivery is becoming more prevalent these days. The main benefit of this method of the medication delivery system is that the substance is only aired when it is required. Because of this, the risk of developing drug resistance, which is common in both preparations for both conventional and sustained release, is minimized. In addition, certain anticancer medications are quite hazardous. In both traditional and sustained release therapy, these medicines cause serious complications. There are now a plethora of FDA-approved chronotherapeutic medications on the market. This treatment is most useful when a long-term effect is just not necessary and medications are harmful. The most important aspect of this formulation's development is determining the circadian rhythm or an appropriate criterion that would set off the drug's release.

Covariance, feedback, and discounting in ratio schedules.

Action-outcome relations in the everyday world are often looser than the relations programmed in the laboratory. Reinforcement theory addressed this looseness by theorizing about "delay of reinforcement." Response-reinforcer interval affects response rate and choice, but need not be thought of as delay. Experiments on temporal discounting are often said to reveal effects of delay also, but the intervals chosen differ from delays, because an outcome after a week, month, or year occurs after life has continued and many events have intervened. They are better called lag intervals. The present experiment studied the effects of varying lag interval on pigeons' responding on ratio-like schedules of food. In a continuous procedure, a lag interval separated pecking that earned food from delivery of the food earned. In one series of conditions, the relation was fixed equivalent to variable-ratio (VR) 40 while the lag interval varied. In a second series, the equivalent VR varied while the lag interval was fixed. The results accorded with matching theory, but with a factor for temporal discounting or loose feedback. The results suggest that both temporal discounting and probability discounting may be characterized within matching theory, but that temporal discounting requires a separate treatment from probability discounting.

New Optimization Method Based on Neural Networks for Designing Radar Waveforms With Good Correlation Properties

Owing to advances in the overall performance and anti-interception capability of radars, the designs of radar waveforms with good correlation properties have been a concern for researchers. In this paper, we propose a novel method based on convolutional neural networks (CNNs) for designing single or multiple unimodular sequences with good auto- and cross-correlation or weighted correlation properties. The framework of the neural networks for sequence optimization is constructed using group convolution and identity mapping, and three different loss functions are presented using different optimization objectives. To illustrate the performance of the proposed method, we present numerous examples, including the design of sequences with low autocorrelation sidelobes in a specified lag interval and a sequence set with good auto- and cross-correlation properties. Moreover, an analysis of the simulations shows that the sequences designed through our method demonstrate better correlation properties than classic algorithms.

Application of Time Series Analysis in Soil Moisture of Fixed Dune on Korqin Sandy Land, Northern China

&lt;p&gt;Time series analysis is a very effective method to analyze the dynamic characteristics of soil moisture at long-term scale. In this study, we have used the time series to analyze the relationship between precipitation and soil moisture on fixed dune at different soil depths (from 0 to 120 cm) during the growing season (from May to September) of 2006-2010 in Korqin Sandy Land, northern China. The results indicate that: (1) The precipitation is a relatively independent time series and has no obvious autocorrelation. Precipitation in an earlier stage has no obvious effect on the later stage in the growing season. (2) Soil moisture in different soil layers has higher autocorrelation; and the autocorrelation of soil moisture in each soil layer is significantly weakened with the increase in time lag interval. (3) The correlation coefficient between soil moisture and precipitation in each soil layer is higher at the time lag interval of k = 0; with the increase in soil depth, the correlation is gradually weakened. (4) The maximum correlation coefficients of soil moisture series and precipitation series in different soil depths were obtained at the time lag interval of k = 0.&lt;/p&gt;&#x0D;

Modeling the Impact of Foreign Investment Flows Taking into Account Time Lags in the Context of their Impact on the Regional Production

Peculiarities of regional processes of foreign direct investment impact on the gross domestic product of Western Ukraine and Chernivtsi region, taking into account a time lag, are reviewed in this article. Considering the fact that investment processes are enough complicated phenomenon to understand in the course of which different kinds of changes occur, the relevance and importance of establishing a pattern of their behavior is increasing. Economical and mathematical tools, in particular Almon distributed lag models which allow to estimate the discrete lag influence of determinants can be used to achieve this. In the course of the study, the Almon distributed lag models were constructed separately for the comparison, time lag interval boundaries were set, the main features of the discrete time lag distribution during the lag period were determined, and the economic and mathematical models of the distributed lag for the effects of foreign direct investment on the gross regional product of Chernivtsi region Western Ukraine were built. On the basis of the obtained results, conclusions about economic multiplier processes of the investment were made in the context of individual territories and the main trends of the investment flow return were defined.

DYNAMICS OF INFLUENCE OF FOREIGN INVESTMENT FLOWS ON REGIONAL PRODUCTION

Peculiarities of regional processes of foreign direct investment impact on the gross domestic product of Western Ukraine and Chernivtsi region, taking into account a time lag, are reviewed in this article. Considering the fact that investment processes are enough complicated phenomenon to understand in the course of which different kinds of changes occur, the relevance and importance of establishing a pattern of their behavior is increasing. Economical and mathematical tools, in particular Almon distributed lag models which allow to estimate the discrete lag influence of determinants can be used to achieve this. In the course of the study, the Almon distributed lag models were constructed separately for the comparison, time lag interval boundaries were set, the main features of the discrete time lag distribution during the lag period were determined, and the economic and mathematical models of the distributed lag for the effects of foreign direct investment on the gross regional product of Chernivtsi region Western Ukraine were built. On the basis of the obtained results, conclusions about economic multiplier processes of the investment were made in the context of individual territories and the main trends of the investment flow return were defined.

The Impact of Unconventional Monetary Policy Tools on Inflation Rates in the USA

This study analyzed the impact of unconventional monetary policy tools on the expected inflation rates that global central banks targeted as a solution for the liquidity trap that many economies fell into during the 2008 financial crisis. The US economy was adopted as a case study for the period 2003 – 2018 with quarterly time series. The study model was based on credit variables (cr), actual federal interest rates (fir), and the monetary mass (M2), as independent variables and their effect on expected inflation rates as a dependent variable using Vector Auto Regression (VAR). The study found that the impact of credit volume changes on expected inflation rates was insignificant. This can be attributed to unconventional monetary policy tools, especially credit facilitation programs, since they aimed at stabilizing financial markets rather than stimulating higher inflation expectations. The zero-interest-rate policy adopted by the US Federal Reserve as of December 2008 contributed to boosting the expected inflation rates as indicated by the results of the study. The parameters were significant, and the relationship was inverse during the second lag interval. Theoretically, this was expected, according to Paul Krugman's model.

Compressive strength of re-vibrated concrete made from pebbles

The search for natural and readily available structural material to meet the growing demand for ecologically friendly and smart structures is an ongoing development. In this background, an experimental study into the compressive strength of re-vibrated concrete made from pebbles as coarse aggregate is presented. Fifty-six (56) concrete cubes were cast adopting a re-vibration time lag interval of 10minutes for one hour, with a target strength of 15N/mm2. This comprised 28 cubes 100% granite and 28 cubes 100% pebbles as coarse aggregates respectively. Two curing ages were considered: 7 and 28 days. Results from the compressive strength tests of the cured specimens showed that: at successive time lag intervals there was an appreciable rise in compressive strength of concrete; observable was also a rise in the compressive strength with an increase of curing age. However, even though the maximum compressive strength of 25.64N/mm2 for 100%granite was achieved, that of 100%pebbles attained 23.33N/mm2, both at 60th minute of re-vibration time lag respectively. Hence, it can be suggested that 100% pebbles replacement for granite can be used to produce concrete with compressive strength of up to 23N/mm2 when revibrated.

Spatial variation in lag structure in the short-term effects of air pollution on mortality in seven major South Korean cities, 2006–2013

Lag is one of the major uncertainties in the heterogeneity of short-term effects of particulate matter with aerodynamic diameter <10 μm (PM10) on mortality. This study aimed to explore spatial variations in extended lag effects of PM10 on all-cause mortality, cardiovascular mortality and respiratory mortality in seven major South Korean cities over a period spanning 2006–2013. We did time-series analysis using generalized linear models and adjusted for temporal trend, day of the week, holiday, influenza epidemic, and weather. Single lag models and distributed lag models were extensively compared, specifically in terms of lag interval, and adjustment for temporal trend. We also conducted a time-stratified case-crossover analysis. Multivariate meta-regressions with city characteristic variables were conducted in order to assess spatial variation in the lag structure. When considering up to previous 45 days of exposure, we found longer lag associations between PM10 and mortality, particularly in all-cause mortality and respiratory mortality. SO2, the ratio of SO2 to PM10 and gross regional domestic product were all found to positively contribute towards the associations between PM10 and all-cause mortality and cardiovascular mortality. Ulsan (Korea's largest industrial city) was found to have the strongest cumulative percentage increases in all-cause mortality and cardiovascular mortality per 10 μg/m3 increase of PM10: 4.9% (95% CI: 2.5, 7.3) and 4.3% (95% CI: −0.9, 9.7) respectively. Busan (Korea's largest seaport city) was found to have the highest cumulative percentage increase in respiratory mortality with an 8.2% increase (95% CI: 2.8, 13.8). In summary, the short-term effects of PM10 on mortality may persist over a period of not just few weeks but longer than a month, and may differ according to regional economy. This study provides public health implication that, in order to minimize the health effects of PM, air quality interventions should focus on not only particulate pollution but also gaseous pollution, such as SO2.

On inferences about lag effects using lag models in air pollution time-series studies

The choice of lag length is a matter of uncertainty in air pollution time-series studies. Lag models and model selections are widely used for inferences about lag effects, but there is lack of discussion on the integration of the two. We aimed to provide theoretical discussion on the performance of lag models, and the impact of model selections on inferences about lag effects. Bias and model selections based upon information criteria, statistical significance, effect size, and model averaging were discussed in the context of lag analysis. A simulation with eight of PM2.5-mortality relation scenarios was also conducted in order to explore the performances of lag models and to compare the model selections. The application of lag models with an insufficient lag interval taken into account (i.e. insufficient lag models) provides biased estimates. We provided features of the model selections and showed their pitfalls in lag analysis of air pollution time-series studies. We also discussed limitations of meta-analysis which fails to consider the application of different lag models in individual studies. To foster exploration on air pollution-lag-response relations with relevant tools, we encourage researchers to compare different lag models in terms of effect estimates and variance estimates, and to report their favored models and competing models together based upon scientific knowledge supporting lag-response relations.

International Application Model Short-Long Term Between GDP and Consumption : Case Study Indonesia

SUMMARY More recently, significant fluctuations in the Indonesian economy justify the need to pay more attention to this issue. In this case, the main purpose of this research is to know the relationship between two issues related to Indonesian macro economy called consumption and GDP for data period during 1967 until 2014. This study investigates the relationship between GDP variables and Indonesian consumption consumption variables using the test ARDL, cointegration and Granger causality. The result of the research can be concluded that, there is long-run equilibrium relationship between GDP and consumption with long-term ARDL model, 10% change of consumption will produce long-term change of 44% in GDP. It is not surprising that there is no short-run equilibrium relationship between GDP and consumption. 10% of consumption will result in a short-term ARDL model change of 95% in GDP. The variables and consumption of GDP are cointegrated in the long run significantly at lag interval 10, whereas the use of lag interval 1 and 5 is not credited in the long run. Using a cointegration test with lag interval 1, 5 and 10 indicates significant for all usage slowness. So it can be summarized in the context of GDP and coordinated short-term economic consumption for all the prevailing interval lags. concluded that long-term causality test results between GDP variables and significant consumption with time intervals 5 and 10. intervals 1, 15 and 20 have no long-term causality relationship between GDP variables and consumption variables. a short-term causal model. With lagging intervals of 1, 5, 10 and 15, there is a short-term causal relationship between the variable GDP and consumption. As for the use of delay interval 20 there is no causal relationship in the short term between the variable GDP and consumption in Indonesia.

Metacognitive control in self-regulated learning: Conditions affecting the choice of restudying versus retrieval practice.

In two experiments, learners studied word pairs one or two times and took a final cued recall test. They studied each pair upon its initial presentation and decided whether they would restudy it later, take a practice test on it later (retrieval practice), or forego all further practice with the pair. Whether learners preferred restudying or testing depended upon conditions. Regardless of whether practice tests were followed by feedback, they chose to take practice tests relatively more often when items were easy and the lag or spacing interval between the first and second occurrence was short, whereas they chose to restudy relatively more when items were hard and the lag was long. That is, they preferred testing under conditions in which successful retrieval on the practice test was likely. In Experiment 2, we varied the number of points each item was worth if recalled on the final test. A high point value led to a marked increase in both the preference for testing when the lag was short and the preference for restudying when the lag was long. Results support the hypothesis that learners appreciate at some level that retrieval practice can be a more effective learning strategy than restudying. However, they appear to believe that successful retrieval is necessary to reap the benefits of retrieval practice. As a consequence, their tendency to choose testing is influenced by conditions (item difficulty and spacing interval) that affect the likelihood of successful practice-test retrieval.

Algorithms for Designing Unimodular Sequences with High Doppler Tolerance for Simultaneous Fully Polarimetric Radar.

Simultaneous fully polarimetric radar uses orthogonal polarization channels to transmit a pair of signals, both of which must have good auto- and cross-correlation characteristics. In this paper, the design of sequences with good correlation properties and Doppler tolerance is investigated. New cyclic algorithms, namely, Cyclic Algorithm-Gradient I (CAGI) and Cyclic Algorithm-Gradient II (CAGII) are proposed to solve the optimization problem. Meanwhile, the sequences designed in this paper have ultra-low auto- and cross-correlation side-lobes in a specified lag interval. Numerical experiments are conducted to demonstrate and validate the superiority of the proposed cyclic algorithms, especially for the measurement of moving targets.

Uterine serous carcinoma: Reassessing effectiveness of platinum-based adjuvant therapy

ObjectiveTwo randomized trials failed to demonstrate efficacy of platinum-based chemotherapy (PbCT) for uterine serous carcinoma (USC). Our objective was to reassess the value of PbCT for patients with microscopic residuum (R0). MethodsProgression-free survival (PFS) after surgery was analyzed for 409 patients and correlated with adjuvant therapies: vaginal brachytherapy (VBRT), external beam radiotherapy (EBRT), PbCT, or combinations. ResultsThe estimated 5-year PFS for stage I (n=209) USC was 65.1% for observation only; 90.7%, VBRT only; and 91.1%, PbCT±VBRT (85% received VBRT); VBRT significantly (P=.004) impacted PFS, but the added value of PbCT remains uncertain. Of 58 stage IIIC, PbCT-treated patients (±EBRT), 5-year PFS was 33.9%; most failures had a vascular disseminated component. Median PFS for 72 stage IV, PbCT-treated patients was 18.6months for R0; 8.0, R1≤1cm residual disease; and 4.6, R2>1cm (P=.008). The progression rate (PR) during 1 to 2year follow-up for R0 was similar to PR during 0–1year follow-up for R1 (P=.31), suggesting recurrences in patients with R0 disease before 2years are likely platinum resistant. PRs during follow-up were nearly identical for R0≥2years and R1≥1year (P=.95), presumably showing limited numbers of platinum-sensitive tumors. ConclusionsA comparison of PR for patients treated with PbCT for stage IV R0 and R1 disease suggested that a 1-year lag interval precedes clinical recognition of PbCT refractory/resistant R0 disease. Most patients treated with PbCT who had microscopic residuum had recurrences within 2years (across stages), emphasizing the need for more effective therapy.

PM2·5 concentration and elderly tuberculosis: analysis of spatial and temporal associations

BackgroundChina periodically has severe ambient particulate matter (PM) pollution, which could cause compromised pulmonary immunity in the population and result in high cardio-respiratory morbidity and mortality. Acknowledging the highly prevalent latent tuberculosis in elderly people, we hypothesise that they are more prone to tuberculosis reactivation in the presence of air pollution. MethodsWe examined the spatial and temporal association between PM2·5 concentration and the number of reported cases of tuberculosis in elderly people aged 65 years and older in Hong Kong. Tuberculosis notification data in 2005–07 were collected from the Chinese Government's TB and Chest Service. Monthly and annual PM2·5 concentration by geographical subdistrict (DCCA) for the corresponding years were derived from satellite images. Age–gender standardised notification rate (SNR) of tuberculosis cases in elderly people was calculated per DCCA/time. Their temporal association with PM2·5 was examined by dynamic linear regression in R, and spatial association by spatial regression in GeoDa. FindingsAmong 17 294 new cases of tuberculosis reported in 2005–07, 6879 (40%) cases were in elderly people (2·69 men for every woman). The mean monthly SNR for elderly men was 35·4 per 100 000 persons (range 25·2–45·3), and the mean of mean PM2·5 in DCCA was 30·5 μg/m3 (16·1–47·1). Temporally, the SNR for elderly men was associated with PM2·5 in lag 0, lag −1 (ie, moving PM2·5 1 month earlier), and lag −4 to −6 months, with the most significant positive association at lag −6 months. However, no temporal association between the SNR for elderly women and PM2·5 was observed. Spatially, the SNR was associated with PM2·5 for elderly men in all 3 years but only for women in 2005. InterpretationWe detected spatial and temporal associations between cases of tuberculosis in elderly men and PM2·5. Tuberculosis reactivation might have occurred after exposure to high PM2·5 in the environment, as inferred from the lag interval of 6 months revealed in our results. The discrepancy between sexes and the effects of potential confounders such as sunshine duration, income level, and locality would need to be further investigated. FundingResearch Grants Council under Theme-based Research Scheme (T32-102/14N).