Senior Bloodwork and Screening: What It Finds, and What It Can't Promise
In 100 older dogs their owners thought were healthy, checks found high blood pressure, murmurs and lumps. What screening finds, and what it can't tell you.
Written by thecanineledger
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A 2017 Belgian study checked 100 older dogs whose owners judged them healthy. It found that “Physical and laboratory abnormalities are common in apparently healthy elderly dogs.” (Willems et al., Journal of Veterinary Internal Medicine 2017).
While that sounds like a strong case for screening, an abnormal result isn’t the same as a disease. The study couldn’t say how many of these findings mattered. This page sets out what screening found, and what it can’t promise.
1. What the checks found
Blood pressure. “Mean SBP was 170 ± 38 mmHg, and 53 dogs had SBP > 160 mmHg.” SBP is systolic blood pressure, the top number.
Heart, teeth and lumps. “A heart murmur was detected in 22, severe calculus in 21 and 1 or more (sub)cutaneous masses in 56 dogs.” Calculus is tartar.
Blood tests. “Thirty‐two dogs had increased serum creatinine, 29 hypophosphatemia, 27 increased ALP, 25 increased ALT, and 23 leukopenia.” Creatinine is a kidney marker. ALP and ALT are liver enzymes. Leukopenia is a low white cell count.
Weight. “Thirty‐nine animals were overweight.”
What owners had noticed. Some had seen changes they put down to age. For example, “13 were more prone to stiffness or lameness, 14 were deaf or hearing less”.
Our note: Blood pressure readings in a clinic can be high from stress. A single high reading may need repeating.
2. What it can’t tell you
Not every finding is a disease. Fourteen dogs with high creatinine didn’t have concentrated urine, which could point to the kidneys. Kidney disease was confirmed in only one. For the others, “no follow‐up information was available, so CKD could not be confirmed.” CKD is chronic kidney disease.
Normal ranges are a problem. RIs are reference intervals, the normal ranges. “Age‐dependent RIs might be warranted, but a major challenge is the selection of an appropriate reference population because older dogs might suffer from subclinical disease.” A result just outside the usual range may or may not matter in an old dog.
Trends matter more than one test. “Ideally, the trend should be followed for an individual animal, so that small, but clinically significant changes can be detected, even when they are still within the RI.”
What it doesn’t show. It was 100 dogs at one Belgian university. It didn’t test whether screening helps dogs live longer or better.
Funding. “This study was supported by a grant from” a pet food company’s Belgian arm. We don’t name it.
Our note: We found no trial showing that routine senior screening improves outcomes.
3. What the guidelines say
Old age isn’t a disease. The 2023 senior care guidelines from the American Animal Hospital Association start from the point that “old age is not a disease.” They say clients “may have the perception that older dogs and cats undergo an unavoidable physical, mental, and behavioral decline attributable simply to old age.” (Dhaliwal et al., Journal of the American Animal Hospital Association 2023, abstract).
How often. Our senior care page covers AAHA’s advice on how often to check.
Our note: We read only the AAHA abstract for this page.
→ Is It Old Age, or Something Treatable? A Guide to Your Senior Dog
4. What to ask your vet
- What are we looking for, and what would we do if we found it?
- Can we compare with last year’s results? A change can mean more than one number.
- If something is borderline, do we retest or treat?
- Should blood pressure and urine be checked too, not only blood?
Our note: These questions are ours.
→ Chronic Kidney Disease: What the IRIS Stage Means · → Pre-Anaesthetic Bloodwork: What It Finds, and When It Matters
5. What we could not verify
| Commonly said | What we found |
|---|---|
| “If my old dog seems fine, it is fine” | Often not. Many findings turned up in dogs their owners judged healthy. |
| “An abnormal result means disease” | Not necessarily. Most findings weren’t followed up, and normal ranges for old dogs are hard to set. |
| “Screening helps old dogs live longer” | Not tested in the study we read. |
| “Stiffness and deafness are just age” | Owners often say so. A vet can tell whether something is treatable. |
Sources
- Willems A, Paepe D, Marynissen S, et al. Results of Screening of Apparently Healthy Senior and Geriatric Dogs. J Vet Intern Med 2017: prospective screening study, 100 dogs, Ghent University. Supported by a pet food company grant
- Dhaliwal R, Boynton E, Carrera-Justiz S, et al. 2023 AAHA Senior Care Guidelines for Dogs and Cats. J Am Anim Hosp Assoc 2023. ⚠️ abstract read. Consensus guidelines
Always confirm with your vet before acting on anything on this page.