Not really a long post, so no worries.
It helps to provide data in the form of a data step so we have something to code against. Instructions here: https://communities.sas.com/t5/SAS-Communities-Library/How-to-create-a-data-step-version-of-your-dat... will show how to turn an existing SAS data set into data step code that can be pasted into a forum code box using the {i} icon or attached as text to show exactly what you have and that we can test code against.
Here is one way that may get you started. The data step is an example of turning your pasted text into a data step that can create usable data.
data have;
infile datalines dlm=',' dsd truncover;
informat record_id comorbid_1 comorbid_2 comorbid_3 comorbid_4 comorbid_5 $25.;
input record_id comorbid_1 comorbid_2 comorbid_3 comorbid_4 comorbid_5;
datalines;
1,dementia,,,pulmonary_disorder,
2,,osteoporosis,dementia,,prostate cancer
3, hepatitis,,pacemaker,dementia,
;
data want;
set have;
array words{5} $25 _temporary_ ('dementia','pulmonary_disorder','osteoporosis','hepatitis','pacemaker');
array c comorbid_:;
cc=0;
do i= 1 to dim(words);
cc= cc+ (whichc(words[i], of c(*))>0);
end;
drop i;
label cc='Comorbidity count';
run;
Some things that a new SAS user will not recognize right away.
The first array, WORDS, contains values that will 1) disappear at the end of the data step, that's what the _temporary_ means, 2) sets the initial (and not changed values) in the (). The number in the {} is how many values you need this has to be large enough to match the number of actual terms you need. The $25 says that the array will hold character values and how long each is. This needs to be at least as long as the longest value you need to search for.
We set the value to 0 before starting the search.
The WHICHC function will search for the first parameter, the current item as we loop through the list of words, and if found in any of the elements contained in the second array c returns which position, 1 to 5 in this case if found or 0 if not found. The comparison of >1 creates a 1 when any match is found so we can add that to the counter variable CC.
Things to consider: if your data entry isn't clean and has values like :Dementia, dementia or dEMENTIA you may want to UPCASE all of the array values so case is not an issue as "dementia" will not match "Dementia" in the WHICHC values.
Second if you have spelling issues: "demensia" for instance, you likely want to fix those first OR you end up with many more values in the WORDS array to include all of the different spellings.
