Tuberculosis (TB) is a preventable infectious disease that confers significant morbidity, mortality, and psychosocial challenges. As TB incidence in the United States (U.S.) decreased from 9.7/100,000 to 2.2/100,000 from 1993 to 2020, the proportion of cases occurring among adults aged 65 and older increased. We conducted a review of published literature in the U.S. and other similar low-TB-burden settings to characterize the epidemiology and unique diagnostic challenges of TB in older adults. This narrative review also provides an overview of treatment characteristics, outcomes, and research gaps in this patient population. Older adults had a 30% higher likelihood of delayed TB diagnosis, with contributing factors such as acid-fast bacilli sputum smear-negative disease (56%) and non-classical clinical presentation. At least 90% of TB cases among older adults resulted from reactivation of latent TB infection (LTBI), but guidance around when to screen and treat LTBI in these patients is lacking. In addition, routine TB testing methods such as interferon-gamma release assays were two times more likely to have false-negative results among older adults. Advanced age was also often accompanied by complex comorbidities and impaired drug metabolism, increasing the risk of treatment failure (23%) and death (19%). A greater understanding of the unique factors of TB among older adults will inform clinical and public health efforts to improve outcomes in this complex patient population and TB control in the U.S.

BACKGROUND: Older adults aged ≥65 years old represent an increasing proportion of tuberculosis (TB) cases in the United States, but limited evidence exists on the characteristics and treatment outcomes that differentiate them from younger adults. METHODS: We evaluated Alameda County TB surveillance data from 2016 to 2019 and abstracted public health charts for older adult TB cases. Clinical presentation and treatment outcomes were compared in older and younger adults (15-64 years), and multivariable logistic regression was conducted to assess risk factors for TB treatment noncompletion among older adults. RESULTS: Of 517 TB cases, 172 (33.2%) were older adults and 101 were ≥75 years old. Compared to younger adults, older TB cases were more likely to be non-US-born, and have diabetes. For diagnosis, older adults were more likely to have negative interferon-gamma release assays (24.6% vs 16.0%; P = .01) and were less likely to have cavitary disease (18.6% vs 26.7%; P < .001). One third of older adults experienced an adverse event; older adults were less likely to complete TB treatment (77.7% vs 88.4%; P = .002) and were more likely to die during TB treatment (16.3% vs 2.9%; P < .01), especially among those ≥75 years old, who had a mortality rate of 22.9%. In multivariable analysis, dementia was significantly associated with treatment noncompletion (adjusted odds ratio, 5.05; 95% confidence interval, 1.33-20.32; P = .02). CONCLUSIONS: Diabetes, negative diagnostic tests, and poor treatment outcomes were more prevalent in older adult TB cases. A greater understanding of their TB presentation and comorbidities will inform interventions to improve outcomes among older adults.

BACKGROUND: Advanced pulmonary tuberculosis (APT) may reflect delays in tuberculosis (TB) diagnosis and contribute to ongoing disease transmission and poor outcomes. We characterized trends and factors associated with APT over ten years in a high TB-burden county within the United States. METHODS: We evaluated microbiologically and clinically confirmed TB cases reported to the Alameda County Public Health Department during 2010-2019. APT was defined as the presence of cavitation on chest imaging and positive acid-fast bacilli sputum smear. Over the ten-year period, we determined overall incidence and annual trends, and conducted multivariable logistic regression to identify sociodemographic and clinical factors associated with APT. RESULTS: We included 997 cases with pulmonary TB, of which 128 (12.8 %) had APT. The 10-year incidence of APT was 8.8 cases per 100,000, with no significant change in proportion over time. The median age of cases with APT were 50 years (IQR 32-61), 68 % were male, and 78.9 % were non-US-born. On multivariable assessment, APT cases were more likely than non-APT cases to use drugs in the past year (aOR 2.43, 95 % CI 1.10-35.09), to have diabetes (aOR 2.51, 95 % CI: 1.59-3.96), and be HIV negative (aOR 9.32 versus HIV positive, 95 % CI 1.87-169.77). While US nativity was not significantly associated with APT, it was an effect modifier. In stratified analysis, APT was more likely among those with drug-use in the last year among US-born, while diabetes was associated with APT among non-US-born individuals. CONCLUSIONS: APT remains a substantial proportion of TB cases. Efforts to increase awareness and access to care are needed for key risk groups including those with recent drug use or diabetes, with consideration of cultural and linguistic factors given differences by US nativity.

CONTEXT: Patients with culture-negative pulmonary TB (PTB) can face delays in diagnosis that worsen outcomes and lead to ongoing transmission. An understanding of current trends and characteristics of culture-negative PTB can support earlier detection and access to care. OBJECTIVE: Describe epidemiology of culture-negative PTB. DESIGN, SETTING, PARTICIPANTS: We utilized Alameda County TB surveillance data from 2010 to 2019. Culture-negative PTB cases met clinical but not laboratory criteria for PTB per US National Tuberculosis Surveillance System definitions. We calculated trends in annual incidence and proportion of culture-negative PTB using Poisson and weighted linear regression, respectively. We further compared demographic and clinical characteristics among culture-negative versus culture-positive PTB cases. RESULTS: During 2010-2019, there were 870 cases of PTB, of which 152 (17%) were culture-negative. The incidence of culture-negative PTB declined by 76%, from 1.9/100 000 to 0.46/100 000 ( P for trend <.01), while the incidence of culture-positive PTB reduced by 37% (6.5/100 000 to 4.1/100 000, P for trend =.1). Culture-negative PTB case-patients were more likely than culture-positive PTB case-patients to be younger (7.9% were children <15 years old vs 1.1%; P < .01), recent immigrants within 5 years of arrival (38.2% vs 25.5%; P < .01), and have a TB contact (11.2% vs 2.9%; P < .01). Culture-negative PTB case-patients were less likely than culture-positive PTB case-patients to be evaluated because of TB symptoms (57.2% vs 74.7%; P < .01) or have cavitation on chest imaging (13.1% vs 38.8%; P < .01). At the same time culture-negative PTB case-patients were less likely to die during TB treatment (2.0% vs 9.6%; P < .01). CONCLUSIONS: The incidence of culture-negative PTB disproportionately declined compared with culture-positive TB and raises concern for gaps in detection. Expansion of screening programs for recent immigrants and TB contacts and greater recognition of risk factors may increase detection of culture-negative PTB.

BACKGROUND: Tuberculosis infection (TBI) and chronic hepatitis B virus (HBV) infection disproportionately affect non-US-born persons. Early identification and treatment are critical to reduce transmission, morbidity, and mortality, but little is known about screening in the United States. METHODS: We conducted a cross-sectional study in a large integrated California health system in September 2022 assessing TBI and HBV screening among persons aged ≥18 years who were born in countries with high TB burden (TB disease incidence rates ≥20/100 000 population) and/or HBV burden (hepatitis B surface antigen seroprevalence >2%). RESULTS: Of 510 361 non-US-born persons born in countries with high TB burden, 322 027 (63.1%) were born in countries with high HBV burden and 188 334 (36.9%) in countries with only high TB burden. Among persons born in countries with high TB and HBV burden, 29.6% were screened for TBI, 64.5% for HBV, and 23.4% for TBI and HBV; 9.9% had TBI and 3.1% had HBV infection. Among persons born in countries with high TB burden only, 27.9% were screened for TBI and 7.5% had TBI. CONCLUSIONS: Among non-US-born persons from countries with high TB and HBV burden, we found low screening rates and elevated prevalence of TBI and chronic HBV infection. Cotesting for TBI and HBV infection in non-US-born persons from countries with high TB and HBV burden might improve outcomes by identifying persons who warrant TBI treatment, HBV treatment, or HBV vaccination. Increased screening is the first step in reducing health inequities and overall disease burden.