Is COPD linked to diabetes? The two conditions are often found together. A 2026 meta-analysis of 31 studies in Frontiers in Endocrinology found diabetes in about 17% of people with chronic obstructive pulmonary disease (COPD), and COPD in about 17% of people with diabetes. The Centers for Disease Control and Prevention (CDC) says people with COPD are more likely to have other chronic diseases, including diabetes. The same analysis found that the links got weaker when other factors were counted, and it rates the certainty of the evidence as very low. The numbers show that the conditions keep company. They do not show that one causes the other.
Key takeaways
- In the 2026 analysis, COPD went with 1.56 times the odds of diabetes (95% confidence interval 1.37 to 1.79), falling to 1.39 (1.01 to 1.77) in adjusted analyses. Diabetes went with 1.29 times the odds of COPD (1.12 to 1.47), and the adjusted result, 1.20 (0.82 to 1.57), was not statistically significant.
- The authors say shared factors such as age, smoking, extra weight, and inactivity drive part of the link. CDC says smoking is the main cause of COPD and raises the risk of type 2 diabetes by 30% to 40%.
- A 2021 analysis of type 2 diabetes found lower lung function in groups of people with diabetes but no difference in the FEV1/FVC ratio, so lower lung function does not mean COPD.
- Steroid medicines are a separate question. The 2026 authors point to steroid courses given during COPD flare-ups, while pooled budesonide trials found no increase in new diabetes with an inhaled steroid.
- New or worsening breathlessness, a lasting cough, or extra mucus is worth a call to your clinician. Sudden or severe trouble breathing needs 911.
COPD and Diabetes: The Short Answer
- They often occur together. About 1 in 6 people in each group had the other condition in the pooled studies.
- The links weaken when other factors are counted. That points to shared causes such as smoking, age, and weight.
- The evidence is rated very low certainty. The studies differ a great deal in how they define and find each condition.
- Smoking connects the two. It is the main cause of COPD and raises the risk of type 2 diabetes.
- Neither condition means you will get the other. A clinician makes each diagnosis from your own symptoms and tests.
What COPD Is
CDC describes COPD as a group of lung diseases that get worse over time, most commonly emphysema and chronic bronchitis. It says nearly 16 million U.S. adults have COPD, and many more do not know they have it. There is no cure for COPD, but it can be treated. Common signs are frequent coughing or wheezing, shortness of breath doing everyday activities, trouble taking deep breaths, and excess phlegm or mucus.
Tobacco smoke is the main cause in the United States, but CDC says nonsmokers can get COPD. Other risk factors include secondhand smoke, workplace or environmental breathing hazards, a family history of COPD, and asthma. Doctors use a breathing test called spirometry to help detect it.
How Often Do They Occur Together?
| Question | What the 2026 analysis found | How to read it |
|---|---|---|
| Diabetes among people with COPD | 17% pooled (24 studies). For type 2 diabetes, 16% | Estimates varied enormously between studies, and the authors call these approximate summaries |
| COPD among people with diabetes | 17% pooled (10 studies). For type 2 diabetes, 19% | In community studies the figure was 15%. In two hospital-based studies it was 36%, which may reflect sicker patients and more testing |
| Odds of diabetes with COPD | 1.56 (1.37 to 1.79). Adjusted: 1.39 (1.01 to 1.77). Type 2 diabetes only: 1.44 (1.02 to 2.03) | An odds ratio above 1 means the odds were higher. The adjusted result only marginally excluded no difference |
| Odds of COPD with diabetes | 1.29 (1.12 to 1.47). Adjusted: 1.20 (0.82 to 1.57), not significant. Type 2 diabetes only: 1.34 (0.98 to 1.71), not significant | The evidence for type 2 diabetes specifically predicting COPD was less consistent |
The authors rate the certainty of evidence as very low because the studies were observational, some had moderate or high risk of bias, definitions of COPD and diabetes varied, and differences between studies were large and unexplained. In both directions, the range of results expected in future similar groups reached or crossed no difference at all (0.99 to 2.47 for COPD and diabetes, and 0.72 to 1.87 for diabetes and COPD).
One genetic study in the analysis, a Mendelian randomization study that uses inherited gene variants to test for cause, found an inverse association between diabetes and COPD (odds ratio 0.87, 0.80 to 0.94). The authors suggest the association seen in large cohorts may reflect residual confounding or extra medical surveillance rather than a true shared genetic cause. That is one study, and it adds to the uncertainty.
Why the Links Weaken After Adjustment
The authors say the apparent link between COPD and diabetes was substantially smaller in adjusted analyses. They attribute that to shared factors, such as age, smoking, extra weight, physical inactivity, and baseline heart and metabolic health, which partly drive the relationship and leave any independent effect of COPD on diabetes uncertain.
Smoking is the clearest shared factor. CDC says smoking is the main cause of COPD and that people who smoke have a 30% to 40% higher risk of developing type 2 diabetes. Our guide on whether smoking affects blood sugar covers the diabetes side.
Does Lower Lung Function in Diabetes Mean COPD?
No. A 2021 analysis of 66 studies of type 2 diabetes found lower FEV1 and FVC in people with diabetes but no difference in the FEV1/FVC ratio. A 93-study analysis described a restrictive pattern, meaning lower lung volumes, as more likely in diabetes. Neither analysis shows that diabetes alone produces COPD, and a clinician interprets your own spirometry results. Our hub article on how diabetes affects the lungs goes through those numbers.
In a UK Biobank study of 16,242 people with type 2 diabetes followed for a median 13.9 years, an obstructive lung function pattern went with a 1.19 times higher risk of heart and blood vessel disease, and a restrictive pattern with 1.47 times, compared with preserved lung function. This is an association. It does not prove that lung function caused the heart outcomes.
Why Might COPD Affect Blood Sugar?
The 2026 authors list ideas and say the relative contributions are hard to separate. In the COPD-to-diabetes direction, they propose that chronic inflammation, low blood oxygen, and weaker muscles promote insulin resistance, and that steroid courses during flare-ups can sharply accelerate new-onset high blood sugar. In the other direction, they propose that long-term high blood sugar harms the smallest blood vessels and lung elasticity. These are possible pathways, not proven ones.
Steroid Medicines and COPD
CDC says medicines can treat symptoms such as coughing and wheezing, and that antibiotics can treat respiratory infections. The sources treat steroid medicines in two ways.
| Form | What the sources say about blood sugar | What to do |
|---|---|---|
| Steroid tablets or injections during a flare-up | The 2026 authors cite steroid-specific meta-analyses and say cumulative exposure during acute exacerbations accelerates new-onset high blood sugar | Tell your diabetes team about any steroid course and ask what to check. Our guide covers whether prednisone raises blood sugar |
| Inhaled steroids used every day | In a retrospective analysis of budesonide trials in COPD, new-onset diabetes or high blood sugar was reported in 1.3% on budesonide and 1.2% on non-steroid comparison treatment (hazard ratio 0.99) | Keep taking medicines as prescribed and ask your prescriber about any change |
These are study findings. They are not dosing advice, and your prescriber chooses the medicine and dose. Our list of medicines that raise blood sugar is a starting point for a pharmacist conversation.
Vaccines, Smoking, and Pulmonary Rehabilitation
CDC says lung infections can cause serious problems for people with COPD and that respiratory disease vaccines can help prevent illness, including COVID-19, flu, and pneumococcal vaccines. The American Diabetes Association (ADA) says all people with diabetes should receive a CDC-recommended pneumococcal vaccine. Which vaccines you are due for depends on your age and history, so ask your clinician. Our guides on vaccines for people with diabetes and the pneumonia vaccine explain the options.
CDC says that for smokers with COPD, the most important part of treatment is to stop smoking. CDC also says pulmonary rehabilitation programs are personalized and can teach you how to breathe better, conserve your energy, and choose which foods and physical activities are right for you. Nicotine replacement products contain nicotine, which raises blood sugar, so CDC advises talking with your doctor about them if you have diabetes.
Symptoms to Report
| What you notice | What the sources say | What to do |
|---|---|---|
| Frequent coughing or wheezing, shortness of breath with everyday activities, trouble taking deep breaths, or extra mucus | CDC lists these as common COPD signs and says to talk with your doctor | Make an appointment |
| Breathlessness at rest, waking at night short of breath, fever, or needing to sleep propped up | MedlinePlus says to see your provider if these occur with breathing difficulty | Call your clinician promptly |
| Breathing trouble that comes on suddenly or interferes with talking | MedlinePlus says to go to the emergency room or call the local emergency number | Call 911 |
| Fast, deep breathing, fruity-smelling breath, vomiting you cannot keep fluids down, or blood sugar that stays at 300 mg/dL or above | CDC lists these as reasons to go to the emergency room or call 911 | Call 911 or go to the emergency room |
Should People With One Condition Be Checked for the Other?
The 2026 authors say their evidence supports, but does not require, integrated heart and metabolic assessment in people with COPD, especially older adults and those with long steroid exposure. They describe blood sugar screening in COPD as a cautious, exploratory measure and not an established standard. For people with diabetes, they say spirometry should be used selectively based on individual risk, such as a heavy smoking history, and not by routine protocol. These are the authors' views. Ask your clinician what makes sense for you, and see our guide on diabetes and shortness of breath for other causes of breathlessness.
Questions to Ask Your Care Team
- Have I ever had spirometry, and should I?
- Do I have any risk factors for COPD, including smoking now or in the past?
- If I have COPD, how often should my blood sugar or A1C be checked?
- If I need a steroid course, what should I check, and when should I call?
- Which vaccines am I due for?
- Is a pulmonary rehabilitation program available to me?
Frequently Asked Questions
Does COPD cause diabetes?
The 2026 analysis found people with COPD had higher odds of diabetes, but the link weakened after adjustment for other factors, and the authors rate the evidence as very low certainty. A link does not show that COPD causes diabetes. Shared factors such as smoking, age, and weight explain part of it.
Does diabetes cause COPD?
The evidence is less consistent. The 2026 analysis found diabetes went with higher odds of COPD, but the adjusted result was not statistically significant, and the type 2 diabetes result was not significant either. One genetic study found an inverse association. A clinician diagnoses COPD from symptoms and spirometry.
How common is COPD in people with diabetes?
The 2026 analysis found COPD in about 17% of people with diabetes and 19% of people with type 2 diabetes. The studies differed greatly, so these are approximate figures. They do not predict your own risk.
Is lower lung function in diabetes the same as COPD?
No. A 2021 analysis of type 2 diabetes found lower FEV1 and FVC but no difference in the FEV1/FVC ratio. Asthma and COPD are diagnosed by a clinician using symptoms and tests such as spirometry, so ask what your own results mean.
Do COPD medicines affect blood sugar?
Some can. The 2026 authors say steroid courses during flare-ups can raise blood sugar, while pooled budesonide trials found no increase in new diabetes with an inhaled steroid. Do not stop or change a medicine on your own, and ask your prescriber or pharmacist how your medicines fit together.
Should I get vaccines if I have COPD and diabetes?
CDC lists COVID-19, flu, and pneumococcal vaccines as ways to help prevent lung infections in people with COPD, and the ADA says all people with diabetes should receive a CDC-recommended pneumococcal vaccine. Ask your clinician which ones you are due for.
References
- He S, Karunakaran M, Rushender R, et al. "Chronic obstructive pulmonary disease and diabetes mellitus: a bidirectional meta-analysis of risk and comorbidity burden." Frontiers in Endocrinology. 2026;17:1912659. Accessed November 2026.
- Centers for Disease Control and Prevention. "About COPD." Accessed November 2026.
- Centers for Disease Control and Prevention. "Diabetes and Smoking." Accessed November 2026.
- Díez-Manglano J, Asín Samper U. "Pulmonary function tests in type 2 diabetes: a meta-analysis." ERJ Open Research. 2021;7(1):00371-2020. Accessed November 2026.
- Zhang RH, Cai YH, Shu LP, et al. "Bidirectional relationship between diabetes and pulmonary function: a systematic review and meta-analysis." Diabetes & Metabolism. 2021;47(5):101186. Accessed November 2026.
- Chen C, Huang Z, Liu L, et al. "Lung Function Impairment and Risks of Incident Cardiovascular Diseases and Mortality Among People With Type 2 Diabetes: A Prospective Cohort Study." Diabetes Care. 2025;48(5):728–736. Accessed November 2026.
- O'Byrne PM, Rennard S, Gerstein H, et al. "Risk of new onset diabetes mellitus in patients with asthma or COPD taking inhaled corticosteroids." Respiratory Medicine. 2012;106(11):1487–1493. Accessed November 2026.
- Centers for Disease Control and Prevention. "Diabetic Ketoacidosis." Accessed November 2026.
- MedlinePlus. "Breathing difficulty." Medical Encyclopedia. Accessed November 2026.
- American Diabetes Association Professional Practice Committee for Diabetes. "4. Comprehensive Medical Evaluation and Assessment of Comorbidities: Standards of Care in Diabetes—2026." Diabetes Care. 2026;49(Suppl. 1):S61–S88. Accessed November 2026.
Next Steps
If you have COPD or smoke, ask your clinician whether spirometry and a blood sugar check make sense for you, and bring your medicine list. Call 911 for sudden or severe trouble breathing.
For adults with type 2 diabetes or prediabetes who want lifestyle education alongside clinical care, the Done With Diabetes™ program, a natural protocol for type 2 diabetes, organizes learning about meals, movement, sleep, and stress. It does not diagnose or treat COPD or diabetes, interpret symptoms or test results, change medicines, or replace your care team.